Groundwater-Dependent 

Ecosystems: Level II 

Inventory Field Guide

Inventory Methods for 

Project Design and Analysis

United States 

Department of 

Agriculture

Forest Service

Gen. Tech. Report 

WO-86b

March 2012
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and employer.

The information contained in this publication has been developed for the guidance of employees of the Forest Service, U.S. Department of Agriculture, its contractors, and cooperating Federal and State agencies. The Forest Service assumes no responsibility for 

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endorsement, or approval of any product or service to the exclusion of others that may be suitable.

Front and back cover photos by William Hansen, forest hydrologist, Francis Marion and Sumter National Forests. Taken May 11, 

2010, at Big Morgan Fen, Francis Marion National Forest in South Carolina.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide iii

Contributors

This field guide was developed under the direction of the Groundwater-Dependent Ecosystems (GDE) Protocol Development Core 

Team with primary contributions from Marc Coles-Ritchie 

of Management & Engineering Technologies International, 

Inc. (METI, Inc.) and Joe Gurrieri (Forest Service, an agency 

of the U.S. Department of Agriculture). Chris Carlson (Forest 

Service) and Steve Solem (METI, Inc.) provided essential 

edits and guidance in the field guide development process. 

Other members of the Core Team, who provided detailed edits 

and recommendations at multiple stages of the field guide 

development, were (of the Forest Service unless otherwise 

noted): Allison Aldous (The Nature Conservancy), Devendra 

Amatya, Trish Carroll, Kate Dwire, Mark Gonzalez (Bureau of 

Land Management, U.S. Department of the Interior), and Barry 

Johnston.

The GDE Protocol Development Steering Team provided 

valuable guidance at multiple stages of the process. That team 

was made up the following individuals (of the Forest Service 

unless otherwise noted): Leslie Bach (The Nature Conservancy), 

Chris Carlson (team leader), Tony Crump, Tony Erba, Russ 

Lafayette, Bill LeVere, Dan Neary, Mike Nevill, Andy Rorick, 

Linda Spencer, Cynthia Tait, and Richard Ullrich. Luke 

Boehnke created the figures, including invertebrate illustrations 

in appendix 12.

Reviews and comments were also provided by members of 

Technical Advisory Teams for the GDE Protocol Development 

project.

Pilot testing of this field guide involved dedicated individuals 

from the following units: Black Hills and Nebraska National 

Forests (Rocky Mountain Region); the Spring Mountains 

National Recreation Area on the Humboldt-Toiyabe National 

Forest (Intermountain Region); Inyo National Forest (Pacific 

Southwest Region); the Malheur, Wallowa-Whitman, and 

Umatilla National Forests (Pacific Northwest Region), Francis 

Marion and Sumter National Forest (Southern Region); White 

Mountain National Forest (Eastern Region); and the Fraser 

Experimental Forest (Rocky Mountain Research Station). 

Acknowledgments

This field guide is a product of a partnership between The 

Nature Conservancy, Oregon Chapter, and the Forest Service 

to improve the awareness and management of groundwaterdependent ecosystems.

Support for development of this field guide was provided by 

Anne Zimmermann, Director of Watershed, Fish, Wildlife, Air, 

and Rare Plants and Tony Ferguson, Former Director of Minerals 

and Geology Management. Joel Holtrop, Former Deputy Chief 

for National Forest System, provided encouragement and 

support along with the Information Resources Decision Board 

in providing project funding. Operational support was provided 

by Patrice Janiga, Ecosystem Management Coordination 

(EMC) Information Assets Portfolio Manager; Mindy Martin, 

EMC Contracting Officer’s Representative; and Jody Rose, 

Intermountain Region Webmaster. The project team members 

and leadership provided by METI, Inc., were essential for successful project management and development of the field guide.
iv Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Foundations

Many questions in the “Pre-Field Survey” and “Field Survey” 

portions of this field guide are based on the Forest Service Site 

General: Field Guide (USDA Forest Service 2009). Attributes 

that are required in Site General are noted as such.

Much of this field guide has been influenced by the foundational work of others in the fields of spring and wetland science 

as represented in the following protocols:

 Field and Laboratory Operations Report for the Oregon 

Wetlands Study (Magee et al. 1995).

 Terrestrial Springs Ecosystems Inventory Protocols

(Stevens et al. 2006).

 National Park Service Mojave Inventory and Monitoring 

Network Spring Survey Protocols: Level I and Level II 

(Sada and Pohlmann 2006 draft). 

 Groundwater and Biodiversity Conservation: A Methods 

Guide for Integrating Groundwater Needs of Ecosystems and 

Species Into Conservation Plans in the Pacific Northwest

(Brown et al. 2007).

 Interim Protocol, Ground-Water Resource Inventory and 

Monitoring Protocol, Level I Spring Ecosystem Inventory 

(Gurrieri 2007 draft).

 Assessing Proper Functioning Condition for Fen Areas in 

the Sierra Nevada and Southern Cascade Ranges in California: A User Guide (Weixelman and Cooper 2009).

 Study Plan: Sampling of the Polygons Photointerpreted for 

Possible Fens on the Grand Mesa-Uncompahgre-Gunnison 

National Forest, Colorado (Johnston et al. 2009 draft). 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide v

Introduction...............................................................................1

Business Requirements Addressed by This Field Guide ...1

Relationships Between Business Requirements and 

Field Guide Levels.....................................................3

Targeted GDEs ..................................................................4

Limitations on Use ............................................................7

Using the Level II Field Guide..................................................9

Skills and Time Required ..................................................9

When To Sample .............................................................10

Preventing Damage to Sites.............................................11

Pre-Field Survey Activities (in office) ....................................13

Site Information...............................................................13

Geographic Information ..................................................14

Mapping...........................................................................16

Route ...............................................................................17

Other Information About the Site....................................17

Field Survey Activities............................................................19

Survey Information .........................................................19

Georeferencing ................................................................22

Geologic Setting ..............................................................23

Images .............................................................................26

Transect Layout ...............................................................29

Vegetation........................................................................30

Soil...................................................................................36

Hydrology........................................................................40

Aquatic and Terrestrial Fauna..........................................46

Natural and Anthropogenic Disturbance .........................50

Management Indicator Tool.............................................52

Post-Field Survey Activities (in office)...................................63

Obtain or Verify Data ......................................................63

Laboratory Analyses........................................................63

Implement Data Management and Interpretation 

Procedures................................................................63

Validate and Confirm Management Indicator Tool 

Entries......................................................................63

Analyze and Evaluate Collected Information..................63

Glossary ..................................................................................65

References...............................................................................69

Appendix 1. Order of Data Collection....................................71

Appendix 2. Job Hazard Analysis...........................................73

Appendix 3. Field Forms.........................................................77

Appendix 4. Site Protection Guidelines..................................93

Appendix 5. Groundwater-Dependent Ecological Systems 

Described in NatureServe................................................95

Appendix 6. Equipment List...................................................97

Appendix 7. Secondary Lithology ..........................................99

Appendix 8. Landform..........................................................107

Appendix 9. Random Number Generation ...........................109

Appendix 10. Plant Labels....................................................111

Appendix 11. Measurement of Discharge at Springs and 

Wetlands........................................................................113

Appendix 12. Identification of Freshwater Invertebrates......119

Contents
vi Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 1

This Level II field guide describes a national protocol to supply 

data used in project identification and planning. Data collected 

through this field guide serve as the basis for the assessment 

of project and activity effects on, and the identification of 

project-level design and mitigation measures for, a specific set 

of groundwater-dependent ecosystem (GDE) types.

This field guide includes all of the components of the companion Level I field guide (GTR-WO-86a), in addition to procedures 

for collecting a broader array of data attributes and greater detail 

for some data attributes. The Level I field guide is intended to 

document the location, size, and basic characteristics of a site 

during a relatively short 2-hour site visit by a trained field crew. 

This Level II field guide is intended to more comprehensively 

characterize the vegetation, hydrology, geology, and soils of 

GDE sites and typically would require 4 to 8 hours at the field 

site by a crew of specialists.

The Level II field guide will enable the user to describe the 

major physical and biological characteristics of GDEs in a 

consistent manner. That consistency will enable the user to 

describe a site’s general condition, monitor major change over 

time, and make comparisons among sites of a certain type or 

within a certain region. This field guide may provide useful information about the presence or distribution of certain species 

(such as invasive or rare plants), but only if they are abundant 

enough to be detected by the procedures established in this 

field guide. Information on species distribution is a secondary 

benefit of this field guide. If inventory or monitoring of specific 

species or communities is the goal, then a more detailed and/or 

targeted set of methods should be used.

Specific examples of what this field guide is designed to be 

used for include the following:

 Characterizing an individual GDE or utilizing an appropriate 

site selection process to characterize the GDEs within an area.

 Collecting baseline information about a particular GDE or a 

defined group of GDEs.

 Monitoring general conditions of an individual site or group 

of sites over time. 

If the objective is to monitor certain conditions of a GDE over 

a period of time, then it will be necessary to develop and use a 

more detailed and site-specific Level III protocol. This Level II 

field guide, however, can be used as a starting point for the 

development of a site-specific Level III protocol that will meet 

the management needs of a particular situation. Assistance with 

the development of Level III protocols is available from the 

National Groundwater Technical Team.

Business Requirements Addressed 

by This Field Guide

Pressure on National Forest System (NFS) lands to supply the 

water, minerals, and energy needed to meet societal needs is 

intensifying. In addition, wildland fire management, hazardous 

fuels reduction, invasive species control, livestock grazing, 

mineral extraction, road and trail management, and ecological 

restoration activities also affect GDEs. Accurate and consistent 

information regarding GDEs and their condition is critical to 

making decisions about and implementing a wide variety of 

the mission responsibilities of the Forest Service, an agency 

of the U.S. Department of Agriculture (USDA). Use of this 

field guide will provide quality-assured data, collected using 

well-documented and consistent methods, to inform policy 

development and project-level decisions about the potential 

effects on GDEs from these activities.

Effective resource management requires a clear understanding of the underlying business requirements for practicing 

conservation. In some instances, policy and direction limit 

management’s ability to respond to identified needs; in others, 

they create an affirmative obligation for the agency to take action to conserve or protect resources and public safety. Business 

requirements stem from two primary sources: (1) regulatory 

and policy requirements and (2) management questions and 

concerns associated with land and resource management plans 

and ongoing or proposed projects/activities (see table 1).

Across the NFS, legal requirements and management issues 

are highly variable, so it is difficult to define a discrete set of 

business requirements applicable to all NFS lands. In several 

instances, laws and regulations provide the opportunity for 

States and tribes to establish additional requirements (these 

could be statutory or rule based) for the protection of resources 

associated with GDEs. This situation creates an even more 

complex set of management requirements. This Level II field 

guide, therefore, is designed to allow for local additions within 

an established national framework.

Introduction
2 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Information used to identify management requirements was 

gleaned from the Forest Service Directives System. Forest 

Service Manual (FSM) 2880 and the “zero chapters” of FSMs 

1900, 1940, and 2500 were the primary sources consulted.

Management requirements applicable to inventory and monitoring of GDEs fall into three groups:

1.	 GDE resource management—The importance of GDEs, 

and their ability to sustain both ecological systems and 

species dependent on groundwater resources, is evident 

in most national forests and grasslands. The collection 

of requirements related to the management of water and 

water uses, and the conservation of threatened, endangered, 

and sensitive species that rely upon these areas, is further 

evidence of their importance. Protection, conservation, and 

restoration of GDEs are often key aspects of decisionmaking 

on NFS lands and a foundation for many land management 

plans. Inventory and monitoring of GDEs are described in 

FSM 2880.

Because of the State-by-State variability associated with 

water rights and uses within the NFS, no attempt has been 

made to summarize such requirements that apply below the 

national level as part of this effort. Readers are encouraged 

to consult FSM 2540 and appropriate regional and forest 

supplements to that chapter to review those requirements.

2.	Planning and environmental compliance—Policy 

and procedures for land management planning and 

environmental compliance activities are outlined in FSM 

1920 and 1950, respectively. Depending on the “vintage” 

of the land and resource management plan for an NFS 

administrative unit, different requirements apply. Field 

users are encouraged to consult their appropriate land 

management plans and the National Environmental Policy 

Act (NEPA) decision documents associated with individual 

uses, activities, and authorizations to determine specific 

design and monitoring requirements.

3.	Resource information management—Forest Service 

Natural Resource Manager (NRM) resource information 

systems, such as NRM-Natural Resource Information System 

(NRIS), NRM-Infrastructure (INFRA), and NRM-Automated 

Lands Program (ALP), provide agencywide data systems 

that comply with departmental and agency requirements. 

NRM applications must be used to store GDE data collected 

under this Level II field guide. NRM applications also 

provide standard analysis and evaluation tools supported by 

the data collection methods described in this field guide.

Management requirements applicable to GDE inventory and 

monitoring can be summarized into the following general points:

 Support an affirmative agency obligation to protect, conserve,

and restore waters, watersheds, and listed wildlife and plant 

species and their habitats and to conserve biological diversity.

Management requirements Management questions

•	 Laws—Establish Forest Service authority and procedural

requirements for managing GDEs.

•	 Regulations—Establish the processes and policy for conducting

land and resource management activities affecting GDEs.

•	 Executive Orders and Presidential Directives—Specify

procedures and requirements applicable to all Government

agencies for the management and protection of GDEs and

associated resources.

•	 Departmental policy—Establishes procedures and policies

for USDA agencies responsible for or potentially affecting GDE

resources.

•	 Agency policy—Establishes agency-specific procedures for

regulatory requirements if not addressed directly through other

means.

Table 1.—Business requirement sources.

•	 Land management plans—Establish desired outcomes (goals

and objectives), standards and guidelines, and monitoring

requirements. Plans include:

§ Ecological context—Are ecological systems functioning and

disturbance processes operating within the natural or desired

range of variation? Are human pressures or changes in ecological systems inducing changes to the ecological context in

which species reside?

§ Species context—Are habitat relationships or ecological

factors affected by management creating risk to species

persistence?

•	 Resource or area plans—Refine interpretations and

requirements for specific resources or areas.

•	 Monitoring—Includes:

§ Implementation—Are projects and activities being

implemented as designed?

§ Effectiveness—Are mitigation measures, best practices, and

design features effective in mitigating anticipated impacts?

§ Validation—Are conservation actions achieving desired

outcomes?
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 3

 Assess and disclose environmental effects associated with 

ongoing and proposed actions and activities, including using 

monitoring data to identify needed adjustments to management practices.

 Use the best available information and science to support 

agency decisionmaking. Collect and maintain resource data 

with known data standards and data quality for use in agency 

decisionmaking processes. Provide for information security.

A detailed review of more than 100 statutes and policies that 

establish management requirements addressed by this effort is 

documented in Groundwater Dependent Ecosystems Inventory 

and Monitoring Business Requirements Analysis (v5.2, January 

30, 2010) and is available for review at http://www.fs.fed.us/

geology/groundwater.html.

Relationships Between Business 

Requirements and Field Guide Levels

Because of the variety of situations encountered on NFS lands, 

it is essential to develop a field guide “package” consisting of 

integrated modules or components that can be matched to a 

local unit’s business requirements and needs. Using different 

inventory and monitoring “intensity levels,” which herein correspond to field guide levels, supports this functionality.

A relationship exists between the types of management requirements and questions being addressed and the data needed to 

address those questions. The amount of effort or “intensity” of 

inventory and monitoring can be categorized into three levels. 

Table 2 describes the level of effort and focus of these levels.

To provide flexibility and ensure appropriate use of the GDE 

field guides, the relationship between business requirements 

(why data are collected) and inventory and monitoring field 

guides (how data are collected) must be clearly described and 

understood. The relationship between business requirements 

and GDE inventory and monitoring field guide (intensity) 

levels is illustrated in figure 1.

The number of management questions considered and the level 

of detail needed to address these questions increases with the 

inventory and monitoring intensity level. Each of the boxes in 

figure 1 represents a grouping of management requirements. 

The level of detail and resolution for data elements needed 

to support the business requirements increases from Level I 

to Level III. For example, the types of information collected 

in Level I for vegetation would be more general than those 

collected in Level II, which would likely be more general 

than those collected in Level III, depending on the particular 

management requirements for which the Level III protocol was 

developed. Specific management questions have been identified 

and associated with business requirements as part of the GDE 

Business Requirements Analysis.

Inventory and 

monitoring 

intensity level

Description

Level I Conducted to characterize GDEs qualitatively

within an administrative unit or management

area. GDE location and extent are spatially 

referenced. Serves as the basis for determining

when GDEs may be affected by proposed actions

or activities or landscape scale change.

Level II Serves as the foundation for assessment of 

project and activity effects and identification 

of design measures. Describes major attributes

including the following: hydrogeologic setting,

aquatic habitat, aquatic and wetland flora and

fauna, and site-affecting disturbances. Can be

used to determine ecological significance of the

GDE and associated resources. Can also be

used as a foundation for designing a long-term

monitoring plan.

Level III Usually conducted in relation to monitoring a major

activity or set of activities affecting GDEs and their

characteristics. Compiles highly quantitative information that describes spatial and temporal variation

in physiochemical characteristics of GDEs. Often

used in the administration of projects or activities and, therefore, is highly site specific.

Table 2.—Descriptions of GDE inventory and monitoring 

intensity levels.
4 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Figure 1.—General relationships between GDE business requirements and field guide levels.

Targeted GDEs

Although many different types of GDEs exist, not all are 

targeted for this field guide. GDEs are ecosystems that are supported by groundwater, which include springs and seeps, cave 

and karst systems, phreatophytic ecosystems, and, in many 

cases, rivers, wetlands, and lakes. This field guide was developed to focus on a subset of nonmarine GDEs, specifically 

springs and groundwater-dependent wetlands (such as fens) as 

illustrated in figure 2. Although this field guide is not intended 

specifically for other types of GDEs (lakes and ponds, streams 

and hyporheic zones, riparian areas, phreatophytic systems, 

or marine systems), parts of this field guide could be used to 

inventory or monitor these systems as well.

In general, where groundwater intersects the ground surface, 

plants and animals that are supported by access to that groundwater will occur, hence the term “groundwater-dependent 

ecosystems.” In some cases, groundwater emerges at a point 

location, usually called a spring or seep, depending on the 

quantity of water available. Herein the term “spring” will be 

used to include both springs and seeps. Springs are always 

GDEs. In the case of wetlands supported by groundwater, 

often there is not a single point where the groundwater flows or 

emerges at the surface; rather, it usually emerges in a more diffuse 

manner across a large area. In some wetlands, however, springs 

emerge within the wetland, or a complex of wetlands and springs 

is present across an area. In many cases, groundwater-dependent 

wetlands, such as fens, are simply springs covered by unconsolidated material (such as glacial deposits, pumice, or colluvium) 

that becomes saturated to the surface. Because an indistinct 

boundary exists between springs and wetlands dependent on 

groundwater discharge, a single field guide was developed for 

these systems. Groundwater emerging at the ground surface is 

the common thread that links these features and their associated 

ecosystems. 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 5

Figure 2.—Diagram of GDE types, with the highlighted types (in box on left) representing those for which this field guide was designed.

It is important to recognize that some wetlands are not supported 

by groundwater, but are formed from water that originates 

exclusively from precipitation and associated surface runoff. 

Such wetlands are called “ombrogenous” hydrological systems 

(National Wetlands Working Group 1997). The meaning of the 

term ombrogenous is “rain fed” according to Mitsch and Gosselink (2007). Ombrogenous wetlands are not the focus of this 

field guide, although the field guide may have components that 

could be used to evaluate ombrogenous wetlands. This field 

guide is intended for wetlands that are supported by groundwater that has come in contact with mineral soils or bedrock. 

Such wetlands are called “minerogenous” hydrological systems 

(National Wetlands Working Group 1997) or “minerotrophic 

peatlands” (Mitsch and Gosselink 2007). Minerogenous wetland 

systems are normally situated at positions in the landscape 

lower than adjacent terrain, such that water and transported 

mineral elements are introduced by groundwater. 

Minerogenous hydrological systems have a strong linkage with 

the physical and chemical nature of the geological environment 

and generally involve the regional groundwater system. They 

are not restricted by local climatic conditions because the groundwater source is generally sufficient to maintain soil saturation 

and, therefore, wetland processes. By contrast, ombrogenous 

hydrological systems (or ombrotrophic peatlands, as described 

by Mitsch and Gosselink [2007]) are not dependent on groundwater and are highly restricted geographically because of local 

climatic conditions. In arid and semiarid regions, many wetlands 

are supported by groundwater. In humid regions, distinction 

of groundwater support of wetlands becomes more difficult. 

Nevertheless, many wetlands in humid regions are highly 

groundwater dependent.

Because it is not always easy to verify a wetland’s dependence 

on groundwater, a site-specific assessment is necessary. One 

source of information to help determine groundwater dependence 

is a publication by The Nature Conservancy (Brown et al. 2007), 

which includes decision trees for determining groundwater 

dependence, such as the one for wetlands, which is adapted for 

this Level II field guide in box 1. 

In summary, this Level II field guide is intended for the inventory 

and monitoring of a subset of GDEs, specifically springs and 

groundwater-dependent wetlands (described in table 3). The 

primary basis for determining which systems to include in the 

GDE field guide is hydrology, specifically the primary water 

source. This field guide provides a very general classification of 

wetlands to indicate which types of wetlands are covered (fig. 2 

and table 3).
6 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Characteristics Springs Peatlands, including fens 

(groundwater dependent)

Other wetlands 

(groundwater dependent)

Hydrology Completely groundwater

dependent

Minerotrophic; always groundwater

dependent

Minerotrophic; depend on groundwater,

precipitation, and sometimes stream

inflow

Water table

position

At ground surface or, for artesian,

a piezometric surface above the

ground surface

At or slightly below surface, or

piezometric surface above the ground

Above or below ground surface; can

fluctuate dramatically; can have periodic

standing water

Soils and peat or

muck depths

Mostly mineral soils; sometimes

a small accumulation of peat

Accumulation of peat or muck up to

several meters; little or no mineral soil

within plant-rooting zone for fens

Usually little or no peat or muck

accumulation; sometimes wood-rich peat

Redox conditionsa Oxic to anoxic depending on

geochemistry and residence

time of water in aquifer

Anoxic slightly below the surface,

leading to the accumulation of peat or

muck

Temporary soil anoxia during times of

high water table or standing water

Water movement

within GDEs

Standing or flowing water Slow to imperceptible flow on surface Periodic standing or flowing water

Water chemistry Highly variable; from acidic to

basic, temperatures vary, can

be thermal, can be saline

Minerotrophic, acidic (poor fens) to

basic (rich fens); can be iron rich or

calcareous

Highly variable, from acidic to basic

Vegetation Graminoids, forbs, shrubs,

bryophytes, and trees; variable

amount of wetland vegetation

Bryophytes, graminoids, and low

shrubs; lichens; sometimes trees;

always wetland vegetation

Tall woody plants and forbs (swamps) or

emergent graminoids and floating aquatic

macrophytes (marshes); mostly wetland

vegetation

Table 3.—Important GDE characteristics and the GDE types covered by this field guide.

a

 Redox (short for REDuction-OXidation) conditions describe a key chemical characteristic in hydrologic systems that controls the availability of 

many elements and the propensity of the system to support the accumulation of organic matter, such as peat and muck. At the ground surface, 

redox conditions are often controlled by the availability of oxygen.

Box 1

Decision Tree for Identifying Groundwater-Dependent Wetlands

(based on Brown et al. 2007, with modifications for this field guide)

4.	 Does the wetland have signs of surface inflow?

No—High likelihood of groundwater dependence

Yes—Go to next question

5.	 Are the wetland soils organic, muck, or peat?

Yes—High likelihood of groundwater dependence

No—Go to next question

6.	 Is the wetland saturated even after surface inputs become dry and

during extended periods with no precipitation?

Yes—

Are the wetland soils clay, hardpan, or impermeable?

No—High likelihood of groundwater dependence

Yes—Low likelihood of groundwater dependence

No—Low likelihood of groundwater dependence

Answer the questions in sequence. A bold answer indicates likely

groundwater dependence, and subsequent questions need not be

answered.

1.	 Is the wetland seasonal?

Yes—Low likelihood of groundwater dependence

No—Go to next question

2.	 Does the wetland occur in one of these landscape settings:

(a) slope break, (b) intersection of a confined aquifer with a slope,

(c) stratigraphic change, or (d) along a fault?

Yes—High likelihood of groundwater dependence

No—Go to next question

3.	 Is the wetland associated with a spring or seep?

Yes—High likelihood of groundwater dependence

No—Go to next question
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 7

Limitations on Use

This field guide is not intended to be used for evaluating some 

specific nonmarine GDEs:

 Groundwater-dependent lakes and associated riparian areas.

 Base-flow streams and associated riparian areas. 

Because of the distinct characteristics of those systems, it is not 

practical to include them in this field guide. It is expected that 

other field guides will address those systems, though they may 

not focus on groundwater conditions and processes. The Forest 

Service is also developing a guide to characterize and monitor 

riparian areas. 

In addition, some wetland systems that look similar to GDEs, 

but are not dependent on groundwater, are not specifically 

targeted by this field guide:

 Bogs.

 Insurgences and sinkholes in karst areas.

 Pocosins—a type of bog in the Southeastern United States 

(described in Richardson 2003).

 Carolina Bays, of the southeastern U.S. Coastal Plain 

(described in Sharitz 2003).

 Other wetlands not supported by groundwater.

Because of the similarities between these systems and GDEs, 

this GDE field guide may have some utility for inventorying 

and monitoring certain components of those systems.

GDE types that would be difficult to sample with this (and 

perhaps any) field guide include geysers, gushets, and hanging 

gardens. This field guide is not designed for underground 

sampling (e.g., in caves), although it would be appropriate to 

use for sampling the surface outflow from caves. Springs that 

include large open water areas (large exposure springs and large 

limnocrenes) could involve substantial safety concerns and 

would be difficult to comprehensively sample with this field 

guide. They require limnological sampling techniques, which 

are beyond the scope of this field guide. 

Settings where this field guide has not been tested include tropical, subtropical, arctic, subarctic, tundra, and permafrost areas, 

which are beyond the scope of this field guide.

Springs

Springs are GDEs where groundwater discharges at the ground 

surface, often through complex subsurface flow paths (Stevens 

and Meretsky 2008). Where a spring emerges from the ground, 

there are communities of plants and animals that depend on 

that water. There are many different types of springs. Springtype descriptions in this field guide are from Springer and 

Stevens (2009). Most spring types—such as outflows from 

caves, helocrenes, hypocrenes, hillslope springs, limnocrenes, 

fountains, and rheocrenes—can be characterized using this 

field guide. 

Wetlands Dependent on Groundwater 

(including peatlands)

The Level II field guide recognizes that a variety of wetland 

types are dependent on groundwater, with many different 

regional characteristics, classifications, and names. It also 

affirms that groundwater dependence spans a continuum from 

completely groundwater dependent to not dependent, with 

varying levels of dependence between these end members. In 

this field guide, however, there is no need to distinguish among 

these different types of groundwater-dependent wetlands. For 

the purposes of this sampling field guide, all are considered 

GDE wetlands, including fens, marshes, swamps, wet meadows, 

and depressional wetlands. 

This field guide, however, does distinguish in some ways 

between fens (i.e., wetlands that have accumulations of peat 

or muck) and groundwater-dependent wetlands that do not 

have peat or muck accumulations. Peat and muck are partially 

decayed plant material that accumulates under saturated conditions where there is little oxygen to facilitate decomposition.

Some names for wetland types apply both to sites dependent on 

groundwater and to others that are maintained by surface water. 

The surface-water supported wetlands, regardless of their name, 

are not the focus of this field guide, although the methods 

described here may be useful to characterize some of them. 

Another way to evaluate these types of wetlands is with the 

criteria for wetland delineation used by the U.S. Army Corps 

of Engineers (1987).
8 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 9

Using the Level II Field Guide

e. Coordinate with other agencies, tribes, States, and 

Forest Service units.

f. Develop quality assurance and control procedures, 

including training and data management.

2.	 Pre-field survey activities—

a. Gather and review background information about 

sites, which is obtained in the office with focus on 

existing maps and remote sensing data (data mining).

b. Establish field logistics and plan for site access, 

including travel and access restrictions. Conduct a Job 

Hazard Analysis, or JHA (appendix 2).

c. Interpret available map and remote sensing images.

3.	 Field survey activities—

a. Use the “Field Survey Activities” part of this field 

guide to conduct data collection. Data can be collected 

on paper field forms (see appendix 3) or with a field 

data recorder (personal data assistant or personal data 

recorder).

b. Apply Management Indicator Tool (on site).

4.	 Post-field survey activities—

a. Obtain or verify data based on location information 

obtained in the field. 

b. Gather laboratory analyses of samples and specimens.

c. Implement data management and interpretation 

procedures.

d. Validate and confirm Management Indicator Tool 

entries.

e. Analyze and evaluate collected information (not 

described in detail in this field guide).

Skills and Time Required

A broad set of skills is necessary to conduct the sampling 

outlined in this field guide, which means that several specialists 

will be needed to collect good-quality data. The skills required 

are summarized in the following list.

The Level II field guide describes specific procedures for field 

data collection for select GDEs; however, a number of important activities precede and follow field data collection. In fact, 

only about one-half of the expected total cost for implementing 

this field guide is associated with field data collection. The 

remainder comes from establishing the objectives; selecting an 

appropriate inventory or monitoring design; training field crew; 

providing quality assurance and control; providing project 

administration and data entry; and, most importantly, analyzing 

and evaluating the information collected. Significant cost 

savings associated with field data collection can be obtained by 

spending time “data mining” before the field activities.

The recommended sequence of activities for implementing 

this field guide is represented in figure 3 and described in this 

section and in appendix 1, Order of Data Collection.

1.	 Study design—Developed by user (not described in detail 

in this field guide).

a. Identify management questions and set inventory and 

monitoring objectives.

b. Determine the area of interest and selection of 

sites—systematic, stratified, or random design, etc.

c. Create the sampling and remeasurement schedule.

d. Identify the relationship to other inventory and 

monitoring programs and data.

Figure 3.—Recommended approach for successfully using this 

field guide. 

Study design

Pre-field survey activities

Field survey activities

Post-field survey activities
10 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

 Office.

§ Geographic Information System (GIS), map interpretation.

§ Data acquisition—from data warehouses, etc. (which 

will likely take a number of days to accomplish).

§ Logistics—transportation, equipment, access, safety, etc.

§ Data entry.

 Field—Botany.

§ Understanding of basic wetland plant ecology.

§ Familiarity with regional flora and proficiency in 

identifying common wetland plant species. Capable 

of sight recognition of dominant species to the level 

of genus and species, provided plants are at the proper 

phenological stage, or capable of sight recognition 

of dominant species to the family, and proficiency in 

keying in the field.

§ Proficiency in keying many unknown plants (e.g., forbs, 

shrubs, trees) to species using regionally appropriate 

floras and diagnostic keys.

§ Ability to distinguish difficult graminoid taxa such as 

Poaceae (grasses), Juncaceae (rushes), and Cyperaceae

(sedges, bulrushes, spikerushes) and to distinguish 

unknown species within these families or genera from 

one another.

§ Ability to collect and press plant specimens so that they 

will be suitable for later identification or verification.

 Field—Animals.

§ Ability to identify aquatic organisms (invertebrates, fish, 

amphibians, etc.) at the family level.

§ Familiarity with quantitative and qualitative methods of 

sampling for aquatic macroinvertebrates.

 Field—Hydrology/Hydrogeology.

§ Ability to measure flows and water quality. 

§ Ability to describe the hydrogeologic setting of the feature, including aquifers, rock types, geologic structures, 

and groundwater flow system. 

§ If monitoring wells or piezometers are to be installed, 

the ability to install, survey, and monitor them.

 Field—Soils. 

§ Ability to describe the soils at a site (by augering soil 

cores, digging pit, or other means).

§ Ability to determine soil texture by feel.

§ Familiarity with standard soil nomenclature, soil stratigraphy, soil morphology, and USDA Natural Resources 

Conservation Service (NRCS) soil taxonomy.

§ Ability to interpret soil features, particularly hydric 

soil features, and infer soil processes within a landform 

setting.

With a team of a few (probably three or four) people who have 

the skills previously outlined, it is anticipated that the field data 

collection described in this field guide will take 1 field day to 

complete. 

When To Sample 

No time is ideal for sampling all the attributes described in this 

field guide. The pros and cons to sampling at different times of 

the year are summarized here.

Winter

 Hydrology—Good time to determine base flow; very difficult to sample water table in deep snow or when ground is 

frozen. (In some settings, groundwater discharge prevents 

ground from freezing.)

 Soil—Very difficult to sample soils in deep snow or when 

ground is frozen. (In some settings, groundwater discharge 

prevents the ground from freezing.)

 Vegetation—Very difficult to identify plants and to quantify 

their abundance.

 Miscellaneous—Might be difficult to access some sites 

(because of snow). In warmer settings, winter might be a 

time to avoid excessive heat; there would probably be less 

disturbance to the site, such as trampling, as a result of field 

guide implementation. Winter use by herbivores can be 

observed.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 11

Early in Growing Season

 Hydrology—Hydrology might be highly influenced by 

weather events (such as snowmelt, high runoff, or rain), 

and water chemistry measurements may be biased by spring 

runoff.

 Soil—Soil can generally be sampled. 

 Vegetation—Difficult to identify plants and to quantify their 

abundance.

 Miscellaneous—Access may be a problem for some sites.

Middle of Growing Season

 Hydrology—Good time to measure water table, although 

flow and water table could be influenced by weather events 

(such as rain).

 Soil—Good time to do soil sampling. 

 Vegetation—Good time to identify plants and to quantify 

their abundance. 

 Miscellaneous—Most sites are accessible. Livestock use can 

be observed.

Late in Growing Season

 Hydrology—Good time for determining groundwater 

influence, although water tables may be lower than they are 

in midseason, making some water chemistry measurements 

difficult.

 Soil—Good time for sampling whole soil profiles. 

 Vegetation—In general, a good time to identify most plants, 

but some plants may have reached senescence, making 

identification difficult.

 Miscellaneous—Good time for observing or measuring 

effects of use by herbivores.

The weather conditions always need to be recorded and considered when evaluating the data. For example, rain can alter pH 

and conductivity and raise the water table.

Preventing Damage to Sites

Springs, fens, and other GDE wetlands are relatively uncommon on the landscape in most areas and are also vulnerable to 

impacts from activities associated with data collection. Small 

GDE sites are particularly vulnerable because the impacts are 

concentrated over a small area. Appendix 4, Site Protection 

Guidelines, outlines specific suggestions for minimizing 

damage to the plants, soils, and hydrologic processes of these 

valuable ecosystems.
12 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 13

Pre-Field Survey Activities (in office)

Site Name 

Description—The site name is a descriptive name for the site, 

such as the common name of a spring or wetland. A portion or 

the entire text of the site name might also be contained in the 

site ID.

Source—The site name can be obtained from the following:

 Maps

§ U.S. Geological Survey (USGS) quadrangle (quad) map 

(these names are also listed in the USGS Geographic 

Names Information System). 

§ Forest Service primary base series maps, which are the 

Forest Service version of the USGS quad.

 Management plans, such as a forest plan, project plan, or 

allotment plan, or existing authorizations that specify the site 

by name.

 If no site name exists in the sources previously listed, then 

create a descriptive name that is representative—and respectful—of the site. It is helpful if this name is unique.

Project Name

Description—The project name is a descriptive term for the 

field guide implementation effort. A project can be a data collection activity containing multiple data collection sites guided 

by a specific purpose. Multiple sites can be within the same 

project. (This is a required field in Site General.)

Source—The project team will create this name. 

Purpose 

Description—The purpose describes the reason the site is being 

sampled. A list of values is included from Site General. (This is 

a required field in Site General.) 

Source—Select one or more purposes from the following list:

q Area assessment.

q Analysis for recreation impacts—human or stock.

q Threatened and endangered species animal habitat 

analysis.

q Big game habitat evaluation.

This section explains what information should be gathered or 

acquired in the office before going out to the field. This information can be compiled in the office using existing data in 

Forest Service NRM applications and through map and remote 

sensing (including photo) interpretation. Some of this information might be updated after the site visit, when field-determined 

coordinates for the site can be plotted on the map.

Obtain information necessary to address some of the Management Indicator Tool statements before going to the site. Review 

the applicable land and resource management plan to determine 

whether the plan recognizes and provides direction for conservation and protection of the site. Identify whether any management activities have taken or are currently taking place at the 

site. Also, identify if any authorized uses are located at the site 

and the terms and conditions of those authorizations.

Site Information

Site Identification

Description—The site identification (ID) is a unique identifier 

for each GDE site. It is useful for managing the data in the field 

and in a database. The same site ID should be used for different 

sampling events at the same site (such as monitoring over time).

Source—The site ID may be obtained from the NRM-Infra

database or the NRM-NRIS Water Rights and Uses database. 

Units may have created their own site IDs in the past. If multiple site IDs exist, then choose the one that best represents the 

site and meets the management needs for which the field guide 

is being implemented (e.g., if the field guide implementation 

is being done to assess effects from water withdrawals, then 

select the existing NRM-NRIS Water Rights and Uses site ID). 

If no site ID exists (or it is unknown), then create a site ID. It 

is highly recommended that the numbers for the region, forest, 

and district form the beginning of the site ID (as recommended 

in Site General). An example would be “040213 Johnson’s 

Spring.” Some site IDs may be only numeric and descriptive 

text would be in the site name (see the following description). 

If the site ID contains descriptive text, then the site name may 

include some of the same text.
14 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

q Ecosystem analysis.

q New ecosystem classification or successional analysis.

q Ecological unit inventory plot.

q Existing vegetation map unit.

q Fire effects or fire history plus fuels.

q Forest plan revision.

q Previous habitat type classification data.

q Integrated multiresource inventory/monitoring.

q Invasive plants inventory.

q Mining claim examination.

q Mining or oil/gas rehabilitation monitoring.

q Threatened and endangered plant species habitat analysis.

q Correlation with permanent timber management plot.

q Range allotment inventory.

q Correlation with regeneration exam/stake rows.

q Range monitoring (i.e., reading, trend, utilization).

q Resource Natural Area and special interest area analysis.

q Research plots.

q Correlation/verification for spectral data/Landsat.

q Correlation with stand exam.

q Correlation with soil survey.

q Vegetation inventory.

q Watershed analysis.

q Wilderness ecology inventory/monitoring.

q General wildlife habitat.

q Watershed inventory.

q Watershed monitoring.

q Operating mine monitoring.

q Oil/gas development.

q GDE inventory or monitoring.

q NEPA.

q Administrative study site.

q Research.

q Water uses and needs inventory.

q State adjudication.

q Determination of waters of the United States.

q Other: ________________.

Geographic Information

State

Description—The U.S. State(s), possession(s), or territory 

where the site is located.

Source—Forest Service NRM-ALP database.

County

Description—The county or counties in which the site is 

located. 

Source—Forest Service NRM-ALP database.

Land Status

Description—The land status where the site is located. (This 

is called “ownership” in Site General and is a required field.) 

Options include Forest Service; U.S. Department of the Interior 

(USDI) agencies, such as U.S. Fish and Wildlife Service and 

Bureau of Land Management; county government; etc. 

Source—Forest Service NRM-ALP database.

Note: It is also useful to determine if the entire site and immediate 

area are under the jurisdiction and management of the Forest 

Service. A related piece of information is whether any activities 

or management on lands outside Forest Service jurisdiction 

are affecting this site. (This information will be necessary to 

answer questions in the Management Indicator Tool, which is 

described toward the end of this document.)

Forest Service Region

Description—The Forest Service region(s) in which the site 

is located. This field is required when land status is Forest 

Service.

Source—Forest Service NRM-ALP database.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 15

National Forest, Grassland, or Prairie

Description—The NFS unit(s) in which the site is located. This 

field is required when land status is Forest Service. (This is called 

“Proclaimed National Forest/Grassland” in Site General.)

Source—Forest Service NRM-ALP database.

Forest Service Ranger District

Description—The ranger district(s) in which the site is located. 

This field is required when land status is Forest Service. 

Source—Forest Service NRM-ALP database.

Grazing Allotment Number

Description—The grazing allotment number. This is useful for 

projects that are focused on grazing issues.

Source—Forest Service NRM-INFRA database.

Grazing Allotment Name

Description—The grazing allotment name. This is useful for 

projects that are focused on grazing issues.

Source—Forest Service NRM-INFRA database.

NRM-INFRA Reference Number 

Description—The NRM-INFRA database reference number 

has been assigned to physical structures or development. 

(If development occurs at the site, it should be recorded in 

the Forest Service NRM-INFRA database that records all 

structures, infrastructure investments, and use authorizations on 

NFS lands.)

Source—Forest Service NRM-INFRA database.

Water Right Number and Status

Description—This number is assigned to a water source by a 

State. The water right status is a determination of the validity 

of the water right that allows the holder to use it in the manner 

represented or prescribed. This is useful for projects that are 

focused on water rights issues. 

Source—Forest Service NRM-NRIS Water Rights and Uses 

database.

Note: It would be useful to determine if there are any outstanding 

claims for water rights by others for this site. (This information 

will be necessary to complete the Management Indicator Tool, 

which is described later in this field guide.)

Watershed(s) Hydrologic Unit Code(s)

Description—The hydrologic unit code (HUC) is a system for 

distinguishing and naming watersheds and subwatersheds (in 

multiple size classes) across the United States. Each hydrologic 

unit is identified by a unique hydrologic unit code consisting 

of 2 to 12 digits based on the 4 levels of classification in the 

hydrologic unit system. We recommend that the 6th-level 

(12-digit) HUC (the subwatershed level) be recorded for each 

GDE site. Multiple HUCs should be recorded if the site is in 

more than one 6th-level HUC. 

Source—The HUC can be can be derived spatially if you have 

good location information (such as Universal Transverse Mercator [UTM] coordinates or latitude/longitude). The following 

USGS Web site describes and delineates HUCs: 

http://water.usgs.gov/GIS/huc.html.

Ecological Unit

Description—“Ecological units are areas of relatively stable 

environments that depict the inherent properties of their ecosystem elements” (Winthers et al. 2005, p. 51). Ecological units 

are divided into hierarchical levels that include section, subsection, landtype association (LTA), landtype (LT), or landtype 

phase (LTP). 

Source—Section and subsection maps can be obtained from 

the ECOMAP 2007 Web site at http://svinetfc4.fs.fed.us/

clearinghouse/other_resources/ecosubregions.html.

Alternatively, NRM-NRIS feature classes for these map units 

can be loaded from the Corporate Data Warehouse directly into 

an ArcMap project by following the directions at http://fsweb.

nris.fs.fed.us/products/Inventory_Mapping/.

LTA, LT, or LTP feature classes can be used if available. If 

the administrative unit does not have LTs or LTPs, and the 

region does not have LTAs already in the NRM-NRIS database, 

then the default is to use the EcoMap Subsection. This can be 

derived spatially if you have good location information (such as 

UTM coordinates or latitude/longitude). 

Ecological System 

Description—NatureServe (2011) provides conservation status, 

taxonomy, distribution, and life history information for more 

than 70,000 plants, animals, and ecological communities and 

systems in the United States and Canada. Although GDEs are 

not explicitly identified in the database, a query of ecological 

systems using terms such as groundwater, seepage, fen, or 

spring will identify most of the GDEs in the inventory area. 

Examples of GDEs in NatureServe include Rocky Mountain 
16 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Subalpine-Montane Fen and Piedmont Seepage Wetland. A 

list of GDEs from the NatureServe database is presented in 

appendix 5. 

NatureServe has developed internationally standardized classifications for terrestrial ecosystems—mid-scale ecological units 

useful for standardized conservation assessments of habitat 

diversity and landscape conditions. Each system encompasses 

complexes of plant communities influenced by similar physical 

environments and dynamic ecological processes, including 

dependence on groundwater. 

Source—The NatureServe Explorer Web site is available at 

http://www.natureserve.org/getData/USecologyData.jsp.

Local Feature-Type Name

Description—This local name is used to describe the type of 

feature being sampled. In some cases, this name can be found 

in the NatureServe list. Some common type names are cienega, 

fen, peatland, swamp, and wet meadow.

This local name can be helpful in understanding the type 

of site and the meaning of regional terms for springs and wetlands.

Mapping

This section describes maps and map sources necessary to 

locate and describe the site. A list of useful geologic map 

resources follows:

 Overview of USGS geology products and work—

http://geology.usgs.gov/.

http://pubs.usgs.gov/of/2005/1305/.

 Link to National Geologic Maps Database Web site for 

downloading by State, etc.—

http://ngmdb.usgs.gov/ngmdb/ngm_catalog.ora.html.

 Link to State geological surveys—

http://www.stategeologists.org/.

Metadata for State geologic data has been standardized over 

select Western States: Arizona, California, Idaho, Nevada, 

Oregon, Utah, and Washington.

For the Pacific Northwest, the major bedrock lithologic units 

can be obtained from a digital map on this USGS Web site— 

http://geo-nsdi.er.usgs.gov/metadata/open-file/95-680/

metadata.faq.html.

USGS Quad

Find the primary USGS topographic quad map where the site 

is located. The USGS system includes quadrangle boundaries 

for the United States available in the 1:250,000, 1:100,000, 

and 1:24,000 scales nationally. The USGS quad can be derived 

spatially once a Global Positioning System (GPS) location is 

established for the site. 

Magnetic Declination

Record the bearing that should be used to adjust for local 

magnetic declination.

Geologic Map Name 

Record the source for geologic mapping. 

Geologic Map Unit 

Determine the geologic unit at the site from the geologic map. 

This unit will be recorded in the NRM-NRIS database. It is 

important for establishing the hydrogeologic setting. This can 

be derived spatially once a GPS location is established for the 

site and a digital geologic layer is obtained.

Land Resource Regions

The Land Resource Region and Major Land Resource Area of 

the NRCS can be obtained from the following Web site:

http://soils.usda.gov/survey/geography/mlra/index.html.

Soil Map Name and Unit 

This is the soil map unit or the soils classification from the 

Terrestrial Ecological Unit Inventory (TEUI) map. This can be 

derived spatially once a GPS location is established for the site 

and a digital soil layer is obtained. It is useful to record the year 

the map was published and the taxonomic unit(s) of the map unit.

Dividing a Site

This field guide is designed to sample sites during a single site 

visit. In some cases it may be necessary to divide large and 

complex sites into smaller units and to sample one or more of 

the units as separate sites over several days.

The reason to divide a site is not to delineate and sample 

certain plant communities or geomorphic surfaces, but rather 

to facilitate sampling of large complex sites or to focus on a 

particular area of interest within a large site associated with the 

purpose of the inventory.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 17

Criteria for subdividing a site depend on the specific purpose 

for conducting the inventory. When conducting an inventory 

in advance of or in association with projects or management 

decisions on activities and uses, it is important not to limit sampling to areas where only direct effects occur or are anticipated 

to occur. In many cases, indirect effects can extend beyond 

the limits of areas directly affected by activities or potential 

projects. In these cases, inventorying the entire site is recommended, which will likely require multiple visits to the site.

If the entire site cannot be inventoried, the site can be divided 

to assess conditions in an area of interest. Regardless of the 

purpose of the inventory, criteria for dividing a site should 

primarily involve geomorphic and topographic factors. The 

use of human-caused boundaries apparent on aerial photos or 

images may fail to capture the full extent of project or activity 

subsurface effects. Geomorphic or topographic breaks can be 

used to identify areas where surface and subsurface effects are 

properly bounded for the purpose of project effects analysis. In 

some cases, vegetation patterns can be used to determine these 

boundaries.

Instruction on dividing a site is also provided in box 2, “Dividing a site,” in the “Area Sampled, If Site Divided” section of the 

Field Survey portion of this guide. 

Route

Coordinates

Determine or estimate UTM coordinates or latitude/longitude 

before the site visit to help with the field crew arrival at the 

site. Update or confirm the coordinates during the field survey.

Location—Driving Route

Provide driving directions from the nearest town to the site (if 

the site is beside a road) or to a place where a vehicle is parked 

before walking to the site (e.g., a trailhead).

Location—Hiking Route

Provide hiking directions from a location where a vehicle is 

parked to the site. Give precise access directions beginning 

with a landmark (e.g., a named point on the topographic map, 

a major highway, marked trailhead) readily locatable on a 

7.5-minute topographic map as the starting point. Use clear 

sentences that will be understandable to someone who is 

unfamiliar with the area and who has only your directions to 

follow. Give distances and use compass directions (true north, 

not magnetic north). When possible, provide a GPS path and 

the ArcMap project name where data are stored for use in 

Trimble or other GPS data logger. Avoid ambiguous words 

such as “above,” “near,” beyond,” “on the back side of,” or 

“past.” If site locations lack major landmark features as guides, 

use township, range, and section information from topographic 

maps. Although the sample sites may not be permanently 

marked, others may want to relocate them for long-term monitoring purposes. Careful documentation of the access route and 

obvious landmarks are, therefore, important. 

Location—Other

If appropriate, provide directions for other means of accessing 

the site, such as by boat or aircraft.

Other Information About the Site

Preliminary GDE Type

Before the site visit, what is the GDE type assumed to be? 

Select one or more from the following list:

 Spring/Wetland Type (modified from Springer and Stevens 

2009)—

§ Cave—Groundwater emerges in or from a cave; common 

in karst terrain.

§ Exposure—Groundwater is exposed at the land surface 

but does not have surface inflow or outflow; occurs in 

karst (sinkholes) and lava flows but could form in other 

types of vertical conduits into an aquifer.

§ Fountain—Cool artesian spring that is forced above the 

land surface by stratigraphic head-driven pressure or 

carbon dioxide (CO2

).

§ Geyser—Intermittent geothermal spring that emerges 

explosively and usually erratically.

§ Gushet—Discrete source of flow pouring from cliff faces; 

typically emerges from perched, unconfined aquifers, 

often with dissolution enhancement along fractures; 

exhibits thin sheets of water flowing over rock faces.

§ Hanging garden or wet wall—Spring that emerges along 

geologic contacts or fractures and seeps, drips, or pours 

onto underlying walls; typically emerges from perched, 

unconfined aquifers in aeolian sandstone units.
18 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

§ Helocrene—Spring that emerges diffusely from lowgradient wetlands; often indistinct or multiple sources 

seeping from shallow, unconfined aquifers (may include 

fens and cienegas).

§ Hillslope—Spring and/or wetland on a hillslope 

(generally 20- to 60-degree slope); often with indistinct 

or multiple sources of groundwater.

§ Hypocrene—A buried spring where groundwater levels 

come near, but do not reach, the surface in arid regions, 

typically due to very low discharge and high evaporation 

or transpiration. In humid regions, these features may be 

equivalent to shallow groundwater areas including wet 

meadows.

§ Limnocrene—Groundwater emerges in pool(s).

§ Mound—Spring that emerges from a mineralized 

mound (usually carbonate), frequently at magmatic or 

fault systems. May also include springs issuing from 

peat mounds. 

§ Rheocrene—Flowing spring that emerges directly into 

one or more stream channels. Spring-fed streams are 

also referred to as springbrooks or spring runs.

§ Other/unknown (describe in notes).

 Note which sources were used to make preliminary GDE 

type determination—

q USGS map.

q National Wetlands Inventory.

q Forest maps.

q Other map.

q Previous forest inventories (vegetation or hydrologic).

q TEUI/aquatic ecological unit inventory.

q Photo.

q Personal account.

q Other: ________________.

Archeological, Paleontological, Cultural, 

or Historic Sites or Use

Research records for cultural resources or historic use (e.g., 

archaeological or paleontological sites) at sites to be inventoried. 

This will help limit damage to important cultural resources.

Available Data

Seek out and list other sources of data that are available about 

the site.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 19

Field Survey Activities

Appendix 6 lists equipment needed to implement this field 

guide. Field forms are in appendix 3. Metric units of measure 

are highly recommended to facilitate data summarization. 

Disturb the site as little as possible while collecting data, as 

described in appendix 4 (Site Protection Guidelines).

Survey Information

Survey Date

Record the calendar month, day, and year the site was visited. 

(This is a required field in Site General.)

Time

Record the time of day for the start and end of the field data 

collection.

Examiners

Record the first and last names of the crew that is doing the 

field data collection. (This is a required field in Site General.)

Weather

Weather can be important when interpreting water chemistry 

and water level information; for example, rain can alter the pH 

and conductivity measurements and raise the water table.

Record evidence of precipitation (rain or snowfall) during the 

sampling visit or evidence of recent rain or snowfall.

q Recent rain.

q Rain during survey.

q Snowfall, hail, or sleet during survey.

q Snow on ground.

q No current/recent precipitation.

Air Temperature 

Record the daytime air temperature at the time of the visit.

Area of GDE

For very small sites, see box 3 before proceeding.

Description—This is a measure of the area or size of the GDE 

site. A GDE site generally has distinctive vegetation that is 

present because of the elevated water table. In some settings, 

such as drier regions, a very clear boundary may exist, which 

is evident from different vegetation or topographic differences, 

between the GDE and the uplands. In other settings, a more 

gradual transition from wetland to upland will occur, with significant zones of transition that include both wetland and upland 

plant species and very little change in slope. In such cases, the 

determination of the boundary of the wetland is somewhat subjective, and must be based, ultimately, on either a judgment call 

or detailed sampling. The following guides will help determine 

the extent of the GDE.

Hydrology—Water on the surface of the ground, or saturated 

ground (not from recent precipitation), can be an indication that 

the area is part of the GDE, although the absence of water does 

not preclude it from being part of the GDE.

Vegetation—The GDE will typically have obligate, facultative 

wet, and facultative wetland species, as distinguished by the 

Wetland Indicator Status of the U.S. Fish and Wildlife Service 

(1988). The edge of the GDE will generally be associated with 

a transition from those wetland species to more upland species. 

The presence of bryophytes could be indicative of a GDE 

wetland, although the absence of bryophytes does not indicate 

that it is not part of the GDE.

Landform—A change in slope (from flatter to steeper) can be 

associated with the edge of the GDE. 

Peat or muck—The presence of peat or muck can indicate a 

GDE wetland. A boundary, with peat or muck on one side and 

no peat or muck on the other, could be an indication of the edge 

of the GDE. The absence of peat or muck does not preclude it 

from being within the GDE.

Spring—A spring will include an orifice, where water emerges, 

and possibly a pool and/or channel. Include the orifice and 

emergence zone, which generally includes obligate and facultative wetland plant species, as distinguished by the Wetland 

Indicator Status of the U.S. Fish and Wildlife Service (1988), 

which are supported by the groundwater discharge or shallow 

water table. A key question in the application of this field guide 

is how much of an associated spring brook should be included 

in the site area. The response can be an arbitrary choice, based 

on a set run-out distance; a subjective decision, based on how 

far the riparian zone appears to be “strongly influenced” by 

the spring; or a more objective decision, such as one used 

in western arid regions, which considers the downstream 
20 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

boundary of the spring to be the point where the spring brook 

water temperature changes by 2 degrees Celsius. Pros and 

cons accompany each of these alternatives. In this field guide, 

20 meters of the run-out stream, or spring brook, are included 

in the site area for sampling. If it is desirable to inventory (or 

monitor) a longer distance of a spring brook, then a stream and/

or riparian protocol should be used to collect the data, which 

would then be considered as a separate (although companion) 

set of data from those collected from the spring as a part of this 

field guide.

How to measure and record—If possible, walk around the 

perimeter of the GDE when measuring or estimating size (to 

avoid excessive trampling). Determine the size of the GDE site 

(including all the spring and wetland features present) by one 

of the following methods (listed in order of highest to lowest 

recommendation): 

1. GPS traverse of GDE edge. (Most GPS units have a feature 

that allows the operator to walk around the edge of the unit 

and determine the area.) 

2. Measure the average width and length (for rectangular 

sites) or diameter (for round sites) using a tape (such as a 

100-meter tape) or a rangefinder. Pacing with a known pacelength may also be done, although it is less accurate.

3. Estimate the size using topographic maps, orthophotos (GIS), 

satellite images (GIS or Google Earth), or aerial photos. 

4. For larger features, where it might not be practical to walk 

the perimeter, it may be possible to sketch the perimeter 

in the GPS/data recorder (if using a unit that allows this 

type of GIS entry), using an image in the background. This 

measurement would require a GPS unit that uses software 

such as ArcPad, which allows the technician to sketch GIS 

features on the screen with aerial images as a background.

5. Estimate the area using the following classes (last resort):

q < 2 m2.

q 2 to 10 m2.

q 10 to 100 m2.

q 100 to 1,000 m2

.

q 0.1 to 0.5 ha.

q 0.5 to 1 ha.

q 1 to 10 ha.

q 10 to 100 ha.

q > 100 ha.

Area Sampled, If Site Divided

If a site is too large to sample effectively, or if the sampling 

needs to be focused on a particular area of interest, then a portion 

of a site may be selected for sampling. Use this approach to 

address specific management needs and not to simply try limiting 

sampling time. Box 2 presents guidance for dividing a site.

Record the size of the area within the site that is actually 

sampled (indicate “all” or the area in square meters).

Dividing a Site

For large or very large sites (such as more than 10,000 square

meters) it may be necessary to divide the site into smaller units to

completely sample one unit during a 1-day visit; other units could

then be sampled during separate visits.

The reason to divide a site is not to delineate and sample certain

plant communities or geomorphic surfaces, but rather to facilitate

sampling of large sites or to focus on a particular area of interest

within a large site associated with the purpose of the inventory.

Criteria for subdividing a site depend on the specific purpose for

conducting the inventory. When conducting an inventory in advance

of or in association with projects or management decisions on

activities and uses, it is important not to limit sampling to areas where

only direct effects occur or are anticipated to occur. In many cases,

indirect effects can extend well beyond the limits of areas directly

affected by activities or potential projects. Inventorying the entire site

is recommended in these cases and will likely necessitate multiple

visits to the site to complete the inventory.

If the entire site cannot be inventoried, the site can be divided to

assess conditions in an area of interest. Regardless of the purpose

of the inventory, delineation criteria for dividing a site should consider

geomorphic and topographic factors as primary delineation criteria.

The use of human-caused boundaries apparent on aerial photos or

images may result in an “under bounding” of potential subsurface

relationships. In general, geomorphic or topographic breaks can be

used to identify areas where surface and subsurface effects are appropriately bounded for the purpose of most project effects analyses.

Box 2

Reference Point

Description—A reference point is a spatial location or point 

on the ground that can be documented with GPS and plotted on 

a map. This point is valuable for plotting the site on a map and 

relocating a site for future sampling visits.

How to measure and record—For springs, the reference point 

should be the spring source (sometimes referred to as the spring 

orifice). For wetlands that are relatively small, the reference 

point could be the center of the wetland or the wettest part of 

the wetland. For larger GDEs, the reference point could be the 

center of the site or some distinguishing feature within the GDE. 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 21

At the reference point, record the latitude and longitude coordinates (see Georeferencing section) that will enable someone to 

return to or near that location. Also, record specific information 

or features that can be used to relocate the exact position of the 

reference point, ideally including a monumented tree, stake, 

fence, large boulder, or the distance and direction from some 

permanent feature such as a road or stream crossing. 

Indicate where the reference point is on the site sketch (see 

Images section). 

Compass Bearing of Long Axis

Identify the longest direction (axis) of the GDE, remembering 

to include such components as 20 meters of any spring brook. 

Place a flag at each end of the long axis (it can be helpful to 

place multiple flags or different colored flags). Record the 

compass bearing of that longest axis. A line perpendicular to 

that compass bearing will be used to determine the direction of 

transects. Note whether magnetic or true north was recorded, 

and, if true north, then note the declination.

Transect Interval

Use the estimated area of the GDE (from previous “Area of 

GDE” question) to determine the transect interval with table 4. 

Some general notes on size:

 Very small sites—Less than about 20 square meters. For 

these small sites, follow the guidance in box 3, “Note for 

Very Small Sites.”

 Small sites—20 to 1,000 square meters. These sites can be 

sampled well with this field guide.

 Medium sites—1,000 to 5,000 square meters. These sites 

can be sampled with this field guide.

Size of GDE (m2) Transect interval (m)

< 20 1.5

20 to 40 2.0

40 to 80 3.0

80 to 150 3.0

150 to 250 4.0

250 to 500 5.0

500 to 750 6.0

750 to 1,000 7.0

1,000 to 1,500 8.0

1,500 to 2,500 10.0

2,500 to 4,000 12.0

4,000 to 6,000 16.0

6,000 to 8,000 18.0

8,000 to 10,000 20.0

> 10,0001 divide into smaller units

Table 4.—Lookup table for transect interval based on site size.

1

 Sites larger than 10,000 square meters require too many transects to 

sample during a single day. Depending on the purpose of the inventory, 

these sites may need to be divided to facilitate inventory. Guidance for 

dividing large sites into smaller areas is addressed in box 2.

Note for Very Small Sites

Very small sites are vulnerable to damage from disturbance caused

by the crew collecting data. Follow these guidelines for sampling very

small sites (see appendix 4):

•	 Walk outside of the GDE site as much as possible.

•	 Record vegetation information from outside the GDE if possible.

•	 Take photos and draw the site sketch from outside the site.

•	 Consider skipping soil core and water table measurements.

•	 Do water measurements carefully.

•	 Make only one trip (or very few) in/across the GDE for

measurements.

Box 3

 Large sites—5,000 to 10,000 square meters. These sites can 

be sampled with this field guide, but some may be difficult 

to sample in 1 day. Consider dividing them into smaller 

units or polygons and then sample one (or more) of those 

polygons as an individual site.

 Very large sites—Greater than 10,000 square meters (1 hectare). 

It would be very difficult to sample these large sites with 

this field guide, particularly in 1 field day. Such large sites 

should be divided into smaller units and then one or more of 

those polygons can be sampled as individual sites.

Table 4 provides the interval between each transect (along the 

long axis). This interval can be marked when the long axis is 

being established, or after. It is useful to label the flags (or use 

different colors) according to transect number, especially for 

larger sites.

Slope

Description—The general incline of the site.

How to measure and record—Record the ratio of vertical rise 

to horizontal distance for the site expressed as percent. This is 

taken either at an average point on the site or as an average for 

a site.

Aspect

Description—The general direction that the landscape faces. 

How to measure and record—Record the azimuth that the 

landscape faces at the center of the site or the majority of the site. 

Azimuth will be recorded from true north in degrees, 0 to 360. 
22 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Surrounding Vegetation

Description—This is a general description of the vegetation 

(generally upland) immediately surrounding the GDE, as 

forested, shrubland, or herbaceous.

How to measure and record—Indicate the type of vegetation 

that is in the area immediately surrounding the GDE site using 

the following list of physiognomic orders from the National 

Vegetation Classification Standards as described in Brohman 

and Bryant (2005).

 Tree dominated—Areas where tree lifeform (see growth 

habit in the NRCS PLANTS database at http://plants.usda.

gov/) has at least 10-percent cover in the uppermost strata 

during the peak growing season.

 Shrub dominated—Areas where shrub and/or subshrub lifeforms are at least 10-percent cover in the uppermost strata.

 Herbaceous/nonvascular dominated—Areas where herbaceous and/or nonvascular lifeforms are at least 10-percent 

cover in the uppermost strata.

 No dominant vegetation type—Areas where vegetation 

cover is at least 1 percent, but the area does not classify as 

tree, shrub, or order herbaceous/nonvascular dominated.

 Nonvegetated—Nonvegetated order usually associated with 

open water or land use dominated, human-modified land, 

such as heavy industrial, commercial, and transportation 

facilities. 

Cut-Level for Plants

Description—This describes which species are included in the 

data collection. Ideally it is desirable to record all species, but 

that is sometimes not feasible because of the time and skill required. A reduced effort is used when there is neither time nor 

interest to record all plant species, but only the more abundant 

species. If a cut-level is used, then plant species with cover 

above the cut-level in the quadrat are recorded and plants below 

the cut-level in the quadrat are not recorded. For example, if a 

cut-level of 10 percent is used, then only species with greater 

than 10-percent cover in a quadrat are recorded, and species 

with less than 10-percent cover in a quadrat are not recorded.

How to measure and record—Note what minimum cover 

per quadrat is used from the options in the following list (from 

Site General, where it is called Species List Complete). The 

5-percent cut-level is recommended to avoid spending too much 

time trying to identify or collect species with very low cover. 

q Complete—All species found in the quadrat recorded 

(code: C).

q Reduced—Species with cover < 1 percent not recorded 

(code: R1).

q Reduced—Species with cover < 5 percent not recorded 

(code: R5) (recommended).

q Reduced—Species with cover < 10 percent not recorded 

(code: R10).

q Reduced—Species with cover < 20 percent not recorded 

(code: R20).

q Reduced by Specified criteria (code: RS).

Relative Area of GDE

Description—The percent of the area covered in general 

categories of GDE settings (complexes of springs, wetlands, 

open water, and other settings).

How to measure and record—Estimate the percent of the area 

within the GDE site that is covered by the following settings 

(must sum to 100 percent):

 Spring emergence.

 Channel (such as spring brook or other channel).

 Wetland/riparian.

 Open water (standing, not generally flowing).

 Other or unknown.

Georeferencing

Horizontal Datum

Description—This is the GPS datum used to record the location information in the field.

How to measure and record—Record the datum for the 

projection at the “reference point.” 

q North American Datum of 1927 (NAD-27).

q North American Datum of 1983 (NAD-83)

(recommended).

q World Geodetic System of 1972 (WGS-72).

q World Geodetic System of 1984 (WGS-84).
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 23

GPS Equipment

Description—The make and model of the GPS equipment.

How to measure and record—Record the make and model of 

the GPS equipment used and the approximate GPS accuracy. 

Universal Transverse Mercator 

Coordinates (from GPS) 

UTM zone—This is the zone for the UTM projection. It can 

be obtained from quad maps or from GPS devices. UTM 

zone coordinates measure in meters east and north from two 

perpendicular reference baselines. 

Easting—This is the distance in meters, east or west, from the 

central meridian of the UTM zone, which is designated at a 

value of 500,000 meters. 

Northing—This is the distance in meters north from the equator 

from the UTM zone origin, which is designated as a value of 

zero meters. (This field guide addresses only north latitudes.)

Latitude and Longitude (from GPS)

Record the latitude and longitude at the reference point. This 

may be recorded either in degrees, minutes, and seconds, or in 

decimal degrees.

 Latitude—degrees:

(Range 0 to 90) The latitude degrees of the site as 

measured by GPS. (Default: north latitude).

 Minutes:

(Range 0 to 59) The latitude minutes of the site as 

measured by GPS. (Default: north latitude).

 Seconds:

(Range 0 to 59.99) The latitude seconds of the site as 

measured by GPS. (Default: north latitude).

 Longitude—degrees:

(Range 0 to 180) The longitude degrees of the site as 

measured by GPS. (Default: west longitude).

 Minutes:

(Range 0 to 59) The longitude minutes of the site as 

measured by GPS. (Default: west longitude).

 Seconds:

(Range 0 to 59.99) The longitude seconds of the site as 

measured by GPS. (Default: west longitude).

 Latitude decimal degree:

Latitude in a degree value. Consists of the latitude in 

degrees to at least 6 decimal places.

 Longitude decimal degree:

Longitude in a degree value. Consists of the longitude in 

degrees to at least 6 decimal places.

Elevation

Description—The elevation of the site.

How to measure and record—Record the elevation with a 

GPS unit at the reference point. Substantial error in GPS measurements may exist, but these data are adequate to characterize 

site elevation. For more accurate elevations, estimate them from 

a 10-meter Digital Elevation Model. Record to within ± 3 meters.

Note how elevation was determined. 

q GPS unit.

q Topographic map (if necessary, interpolate between two 

contour intervals).

q Other: ________________.

Geologic Setting

Evidence of Groundwater

Record the evidence that this ecosystem is groundwater 

supported. Use the decision tree in box 1 to help with this 

determination. Multiple answers are allowed.

q Flow from a spring source, contact, joint, or fault—

indicating spring. 

q Peat or muck accumulation significant.

q Standing water.

q Wetland vegetation.

q Other: ________________.
24 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

GDE Type

Description—A general categorization of the GDE types at the 

site.

How to measure and record—Record the primary (dominant) 

GDE type and secondary GDE types present at the site. Only 

one primary type is recorded, but multiple secondary types can 

be recorded.

 Spring/wetland type (modified from Springer and Stevens 

2009):

§ Cave—Groundwater emerges in or from a cave; common in karst terrain.

§ Exposure—Groundwater is exposed at the land surface 

but does not have surface inflow or outflow; occurs in 

karst (sinkholes) and lava flows but could form in other 

types of vertical conduits into an aquifer.

§ Fountain—Cool artesian spring that is forced above the 

land surface by stratigraphic head-driven pressure or 

CO2

.

§ Geyser—Intermittent geothermal spring that emerges 

explosively and usually erratically.

§ Gushet—Discrete source of flow pouring from cliff 

faces; typically emerge from perched, unconfined 

aquifers, often with dissolution enhancement along 

fractures; exhibit thin sheets of water flowing over rock 

faces.

§ Hanging garden or wet wall—Spring that emerges along 

geologic contacts or fractures and seeps, drips, or pours 

onto underlying walls; typically emerges from perched, 

unconfined aquifers in aeolian sandstone units.

§ Helocrene—Spring that emerges diffusely from lowgradient wetlands; often indistinct or multiple sources 

seeping from shallow, unconfined aquifers (may include 

fens and cienegas).

§ Hillslope—Spring and/or wetland on a hillslope 

(generally 20- to 60-degree slope); often with indistinct 

or multiple sources of groundwater.

§ Hypocrene—A buried spring where groundwater 

levels come near, but do not reach, the surface in arid 

regions, typically due to very low discharge and high 

evaporation or transpiration. In humid regions, these 

features may be equivalent to shallow groundwater areas 

including wet meadows.

§ Limnocrene—Groundwater emerges in pool(s).

§ Mound—Spring that emerges from a mineralized 

mound (usually carbonate), frequently at magmatic or 

fault systems. May also include springs issuing from 

peat mounds. 

§ Rheocrene—Flowing springs that emerge directly into 

one or more stream channels. Spring-fed streams are 

also referred to as springbrooks or spring runs.

§ Other/unknown (describe in notes).

Geologic Structure Type

Description—The geologic structure type is the kind of 

structure that may be controlling the flow of groundwater to the 

GDE, such as a geologic contact or fault plane. Many GDEs 

occur on geologic structures because they can create preferential pathways for the flow of groundwater. This is helpful for 

understanding the hydrogeologic setting of the site and from 

where groundwater is sourced.

How to measure and record—Record the type of geologic 

structure (preferential groundwater flow path) that is discharging water to the site. Observe the geologic units and geologic 

structure and compare that to a geologic map. Record your 

conclusions based on the following list: 

q Bedding—Planar surfaces that visibly separate layers of 

stratified rock.

q Contact—Planar surfaces that separate different rock 

units.

q Fault—Fracture or a zone of fractures along which there 

has been displacement.

q Fracture—Fracturing in rock, without displacement.

q Lineation—Any linear structure on the ground surface (in 

general, identified on aerial photography).

q Conduit—Tubular opening, common in karst terrain.

q Unknown.

Indicate source of conclusion:

q Observation.

q Geologic map.

q Other: ________________.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 25

Surficial Material 

Description—This is the kind of unconsolidated material occurring at the surface. Many GDEs, particularly fens, develop 

on unconsolidated surficial materials. The type of material can 

influence the water chemistry and ecology.

How to measure and record—Record the kind of material 

occurring at the surface. Surficial materials are defined as 

nonlithified, unconsolidated sediments. They are materials 

produced by weathering, sediment deposition, biological 

accumulation, and human and volcanic activity. They include 

residual materials weathered from rock in situ; transported 

materials composed of mineral, rock, and organic fragments 

deposited by water, wind, ice, gravity, or any combination 

of these agents; accumulated materials of biological origin; 

materials moved and deposited by human actions; and unconsolidated pyroclastic sediments. Record the primary surficial 

material; secondary surficial materials may also be recorded.

q Alluvium—An unconsolidated accumulation of streamdeposited sediments, including sands, silts, clays, or 

gravels.

q Colluvium—Soil material and rock fragments moved 

downhill by creep, slide, slough, or local wash and 

deposited at the base of steep slopes.

q Eolian deposit—Wind-deposited sediments.

q Glacial deposit—Includes unsorted and unstratified till, 

including moraines, which are generally exposed in the 

uplands; and glacial meltwater deposits of sorted and 

stratified deltaic, stream, and lake sediments.

q Human-caused or constructed—Natural and manmade 

materials that have been artificially emplaced.

q Lacustrine sediments—Sediments deposited in lakes.

q Landslide deposit—Sediment deposited by downslope 

movement of a sorted or poorly sorted mass of soil or 

rock of mixed grain sizes, including rock falls, slumps, 

mud flows, debris flows, and earth flows.

q Marl—A friable deposit consisting of clay and calcium 

carbonate.

q Residuum—Weathered bedrock.

q Talus deposit—An accumulation of angular rock debris 

at the base of a cliff or steep slope that was produced by 

physical weathering.

q Volcanic unconsolidated material—Ash or mudflow.

q Rock—Bedrock with no surficial material present.

q Tufa or travertine deposits—Travertine is a sedimentary 

rock, formed by the precipitation of carbonate minerals 

from solution in ground and surface waters, or geothermally heated hot springs. Similar, but extremely porous, 

deposits formed from ambient temperature water are 

known as tufa.

q Other/unknown.

Lithology, Primary (groundwater 

source aquifer)

Description—Primary lithology describes the geologic materials such as bedrock or other surficial materials under a site. The 

groundwater source aquifer refers to the aquifer from which the 

groundwater is emanating. The primary lithology is generally 

the groundwater source aquifer. Primary lithology is useful for 

understanding the groundwater flow patterns. The location and 

hydrology of GDEs are controlled by the geology, and the type 

of rock can influence the water chemistry and ecology of the 

feature.

How to measure and record—If evidence in the field exists, 

then record one of the following primary lithology descriptors. 

If no evidence in the field exists, then answer this question in 

the office using the electronic resources listed in the “Mapping” 

section. If the groundwater emerges from a talus or other unconsolidated material at the base of a slope, then try to determine 

the upgradient geologic unit from which the groundwater is 

originating. The important bedrock lithology or geologic unit is 

the one supporting the aquifer that supplies water to the feature.

q Igneous extrusive.

q Igneous intrusive.

q Sedimentary.

q Metamorphic.

q Undifferentiated—Rocks for which finer age divisions are 

not specified on the map, small areas of rocks of different 

ages are too close together to be shown at the scale of the 

map, or the exact age relationships of the rocks in a given 

area may not yet have been determined.

q Unconsolidated—Loose sediment, lacking cohesion or 

cement.

q Unknown.

q Other: ________________.
26 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Indicate whether the primary lithology (noted previously) is 

also the groundwater source aquifer.

q Yes.

q No.

q Unknown.

Level of certainty for groundwater source aquifer.

q Known—Based on site investigation.

q Assumed—Based on professional opinion.

q Unknown—Needs further investigation.

Lithology, Secondary

Description—This is a finer scale description of the lithology 

of rock units occurring at the site and is tiered to the primary 

lithology of the aquifer from which the groundwater is emanating, or the original rock type that weathered to form the parent 

or surficial material. 

How to measure and record—If evidence in the field exists, 

record the secondary lithology (tiered to the primary lithology) 

from the list in appendix 7, which is from Site General (USDA 

Forest Service 2009).

Landforms

Description—The location of many GDEs is related to the 

local geomorphologic history and existing landforms. GDEs 

may develop within, or adjacent to, certain types of landforms 

(e.g., at the toe of slumps and on stream terraces). 

How to measure and record—Use a geologic map, air photo 

interpretation, satellite imagery, or field observations to select 

a “process/landform” from the list in appendix 8, which is from 

Haskins et al. (1998). Record the primary landform; secondary 

landforms may also be recorded.

Images

Photos 

Description—Photos of the site are taken and stored electronically. Photos help to visualize the site, to compare one site to 

another, and to record change over time.

How to measure and record—A brief description of methods 

for photo point monitoring is presented here, while more 

detailed instructions can be found in the Forest Service, 

Pacific Northwest Research Station publication Photo Point 

Monitoring Handbook (Hall 2001). One photo can represent 

multiple points, as long as they are all noted.

Note: Photo points can be captured in a GPS and marked as 

such. The digital image can be stored with that point location 

and viewed by simply clicking on a point within a GIS project 

file.

Instructions for photos—

 Record the distance from camera to photo point (so that 

the same distance can be used in the future when the photo 

points are repeated)—

§ There are two ways to achieve this:

" Always take photos a set distance from an object 

in the photo, such as a measuring staff (or folding 

2-meter board).

or

" For each photo, record the distance from the camera 

to an object in the photo, such as a measuring staff.

 Height of camera—

§ Always take the photo at a height of 1.5 meters above 

the ground.

 Light and time of day—

§ If possible, take photos in the middle of the day rather 

than early in the morning or late in the afternoon.

§ If possible, do not take photos looking into the sun.

 Photo identification board/card/sheet— 

§ In each photo (top corner is recommended) include 

something (board, card, or sheet) with the following 

information written on it:

" Site ID.

" Photo number.

" Date.

 Note the following on a photo form—

§ Info from photo identification card (site ID, photo 

number, date).

§ What is in the photographed scene. 

§ Distance from camera to object in photo.

§ Orientation of camera (compass bearing).

§ Time of day.

§ Weather.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 27

 To improve comparability for rephotography, take photos 

as close as possible to the time and date of the previous 

photos.

Take photos for the following locations (some photos may 

serve more than one purpose, as long as each is noted). 

q Reference point (defined previously).

q Each transect, from starting point, with view of entire 

transect. 

q Center of site.

q Water measurement locations.

q Soil core locations.

q Spring source (if applicable).

q For springs with outflow channels—

§ Looking downstream, standing at/near source.

§ Looking upstream (or uphill), standing at/near 

source.

q Overview, from a hill (if possible).

Site Sketch Map

Description—This is a hand sketch of the site that includes 

sample locations, important features, etc. The sketch map is 

useful for understanding the site and to facilitate relocating 

the site on return visits. The sketch is also useful where GDE 

sites may be close to one another and map/GPS coordinates 

weakly describe the relative location of sample sites. 

How to measure and record—Draw a sketch (hand-drawn 

map or electronic) of the site (see example in figure 4). One 

way to do this is to use an aerial photo to trace the boundary 

of the GDE onto a blank page that then becomes the sketch 

of the site. Graph paper is useful for drawing the sketch map, 

using the lines as known distances. The items in the following 

list should be captured and documented on the sketch map for 

each site. 

q Reference point (described previously).

q Approximate locations/dimensions of major geomorphic 

surfaces.

q Springs—

§ Spring source. 

§ Channel locations.

§ Structures including spring boxes, troughs, and 

pipelines.

§ Pool location, if limnocrene.

q Areas of standing water (indicate deepest part).

q Location of measurements—

§ Transects.

§ Soil holes.

§ Water table measurement locations.

§ Wells/piezometers.

§ Water quality samples.

q Structures or other man-made features, such as roads, in 

or adjacent to GDE.

q Indication of north (true recommended, or magnetic).

q Indication of scale.

q Boundaries of GDE, or the delineation of the area 

sampled if only a portion of the site was sampled (the site 

was divided).
28 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Figure 4.—Site sketch map example.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 29

Transect Layout

Transects across the GDE site (extending from one edge of 

the GDE to other) are used to sample vegetation, soil, and 

hydrology of the site (figs. 5 and 6). A systematic sampling 

approach (Elzinga et al. 1998) will be used, which distributes 

transects across the site to obtain data that represent the entire 

site. The number of transects will be a function of the size 

of the site (fewer transects for small sites and more transects 

for larger sites). The objective is to sample the entire site to 

accurately characterize it and potentially serve as a foundation 

for developing future monitoring plans.

Detailed instructions on how to sample vegetation, soil, and 

water along the transects are described in the Vegetation, Soil, 

and Hydrology sections of this field guide.

For sites that are narrow or linear, such as spring brooks or 

those located in canyons, transects will be short but frequent 

(fig. 6).

Transect Establishment

In most cases, the long axis will be a single straight line. In 

cases where the site has a distinct bend, a kink or dogleg in the 

long axis can be made. It is recommended that no more than 

one kink be included in the long axis. As much as possible, 

kinks in the long axis should be avoided because of the confusion they could create for sampling and resampling. No kink in 

individual transects should exist.

The following rule set will be followed to determine which 

transect will be number 1. Use a compass to determine which 

end of the long axis is closest to due south. That will be the 

0-point of the long axis, and the first transect (transect # 1) 

will be set up in relation to that point. An exception to this can 

be made for long linear sites, such as a spring and associated 

spring brook, in which case the transect closest to the initial 

spring orifice should be transect number 1 and subsequent 

transects would extend downgradient.

Randomize the placement of the first transect along the long 

axis by picking a random number (see appendix 9, Random 

Number Generation) between 1 and the interval distance between 

transects (0 is not an option because that could put the entire 

transect along the edge of the GDE). For example, if the interval between transects is determined to be 10 meters, then pick a 

random number between 1 and 10 and place the first transect at 

that distance along the long axis and place subsequent transects 

every 10 meters (the set interval distance for this example).

To determine which side of the GDE will be the 0-point, use the 

following rule: standing at the 0-point of the long axis and facing in the direction of the long axis, the 0-point for all transects 

would be to the left side of the long axis.

Transects extend across the GDE from one edge to the other 

and may not cross or overlap. Use a compass bearing set 

perpendicular to the long axis of the site to lay out all transects, 

which will force them to be approximately parallel. The only 

exception to no crossing or overlapping transects is for sites 

with a kinked long axis. When establishing the edge of the site 

for each transect, it is not critical to be get it exactly “right,” 

because this is not delineation for regulatory purposes. It is 

important, however, to ensure that the transect is not too short, 

resulting in the omission of obvious GDE-related vegetative 

and soils features along the transect.

Figure 5.—Layout of transects at a small- to medium-sized 

GDE site. The soil and water table measurement locations are 

at 50 percent, 20 percent, and 65 percent of the distance along 

the transects. 

Figure 6.—Layout of transects at a very narrow GDE site. The 

soil and water table measurement locations are at predetermined 

distances along the transects.
30 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Unusual Sites

Sites on walls, such as gushets and hanging gardens, cannot 

be sampled easily with this Level II field guide. In such 

cases, project the locations of transects and quadrats onto the 

wall, and from a distance, record whatever vegetation can 

be observed (preferably species; otherwise genus, family or 

lifeform). Other suggestions include—

 Take pictures.

 Use binoculars.

 Use a range finder.

Vegetation

Vegetation data are collected along transects through systematic 

sampling as described previously in the Transect Layout section. 

The transect line will be used for the following: quadrats to 

record the cover of plant species and ground cover, a line 

intercept of woody plant canopy, and a belt transect to record 

tree data (fig. 7). A search for additional species will be done 

in different areas than the transects to provide a more complete 

species list and to detect particular species of interest (SOI), 

such as invasive or endangered plants. 

A list of equipment for vegetation data collection is in 

appendix 6, Equipment List.

Quadrats

A quadrat that is 0.5 meters x 0.5 meters (fig. 8) will be used to 

record cover of plant species.

Quadrat Interval

Use the size of the GDE recorded in the “Area of GDE” question (previous) to determine the quadrat interval with table 5. 

This will result in about 10 to 30 quadrats at a site.

Quadrat Placement

For each transect, select a random (see appendix 9 for random 

number generation) starting distance from the 0-point (edge of 

GDE) to determine where to place the first quadrat. To do this 

randomly, select a number between 0 and the interval distance 

(minus 0.5 meters) using 0.5-meter increments as the options. 

For example, if the interval distance is 2 meters then pick a 

random number between 0 and 1.5 meters (the options would 

be 0, 0.5, 1, 1.5). If 0 is selected, then the quadrat would start 

at 0 (edge of GDE) and extend into the GDE. Then the next 

quadrat would start at the 2-meter point. If 1.5 was randomly 

selected, then the first quadrat would be at 1.5 (extending to the 

2-meter point) and the next quadrat would start at 3.5 meter. 

After the first quadrat location is randomly selected, the set 

interval is used for all subsequent quadrats on that transect. 

Because of the random starting point, every spot along the 

transect has an equal likelihood of being selected. This 

process is repeated for each transect.

Figure 8.—Illustration of quadrat frame for vegetation 

sampling.

Figure 7.—Transect showing layout of vegetation data 

collection: quadrat for low vegetation, line intercept of woody 

plants, and belt transect for tree count. Example of soil and 

water table measurement location (20 percent distance in this 

case) is also shown.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 31

Lay out a tape if possible or use a meterstick (in dense shrub 

communities) to measure the intervals of quadrats. Walk to one 

side of the transect line and place the quadrat at the appropriate 

point before walking on that spot (to facilitate identification 

and cover estimation). The quadrat starts at the point corresponding to the distance number along the transect, and extends 

0.5 meters from that point. The center of the quadrat frame 

is placed along the transect line. Where you are close to the 

edge of the GDE, do not record data for a quadrat if part of it 

extends outside the GDE site.

The quadrat location is never to be moved from the systematically determined location, regardless of where it lands. If 

a quadrat lands on open water (such as a pond) record any 

emergent or visible aquatic vegetation; if no vegetation exists, 

then just record “no vegetation.” If the quadrat lands on the 

trunk of a tree, the tree is not recorded (it will be recorded in 

the line intercept). The only exception would be if the quadrat 

landed where a hole had been dug for soil or hydrologic 

measurements, in which case the quadrat should be moved just 

far enough along the transect to exclude the hole.

Setting of Quadrat

Description—This provides a general idea of the setting of 

each quadrat, which can be used to group species data from 

quadrats into subsets of the site. Grouping data by setting can 

allow the user to compare the existing vegetation with the 

expected vegetation for the setting.

How to measure and record—Indicate the setting of each 

quadrat, from the following list of recommended categories 

(other settings may also be recorded): 

 Bedrock.

 Channel dry.

 Channel flowing.

 Channel margin.

 Edge of GDE.

 Organic ooze.

 Other.

 Pool.

 Riparian zone.

 Spring mound.

 Spring source.

 Terrace lower.

 Terrace upper.

 Unfocused sheet (madicolous) flow.

 Upland.

 Wetland flat.

 Wetland sloped.

 Wall dry.

 Wall wet.

Vegetation Cover in Quadrats

Description—This is a measure of the abundance of plant species in quadrats distributed systematically along transects. Plant 

species cover is one of the fundamental attributes of GDEs. The 

plant species cover data from the quadrats can be used to characterize the vegetation for the entire site. Plant species cover 

data can be used to understand levels of disturbance in the past, 

evaluate current condition, and monitor the site over time.

How to measure and record—Record the full species name or 

NRCS code of plants with cover in the 0.5 x 0.5 meter quadrats. 

Include all herbaceous (nonwoody) vascular plant species (including tall herbaceous species), very low-stature woody plants 

(sometimes referred to as dwarf shrubs, sub-shrubs, or matted 

plants) and tree seedlings. Low-stature woody plants, for this 

field guide, are considered to be woody species that typically 

grow below 0.5 meter. It is not possible to list all such species, 

but examples of low-stature woody plants that might be found 

in a GDE are— 

< 20 1.5 1.0

20 to 40 2.0 2.0

40 to 80 3.0 2.0

80 to 150 3.0 2.0

150 to 250 4.0 3.0

250 to 500 5.0 4.0

500 to 750 6.0 5.0

750 to 1,000 7.0 6.0

1,000 to 1,500 8.0 7.0

1,500 to 2,500 10.0 9.0

2,500 to 4,000 12.0 10.0

4,000 to 6,000 16.0 12.0

6,000 to 8,000 18.0 14.0

8,000 to 10,000 20.0 16.0

> 10,0001 Divide into smaller units

Table 5.—Lookup table for quadrat interval determination.

1

 Sites larger than 10,000 square meters require too many quadrats 

to sample during a single day. Depending on the purpose of the 

inventory, these sites may need to be divided to facilitate inventory. 

Guidance for dividing large sites into smaller areas is addressed in 

box 2.

Size of GDE (m2

) Transect interval (m) Quadrat interval (m)
32 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

• Ampelopsis arborea (peppervine).

• Arctostaphylos alpina (alpine bearberry).

• Empetrum nigrum (black crowberry).

• Gaultheria humifusa (alpine spicywintergreen).

• Kalmia microphylla (alpine laurel).

• K. polifolia (bog laurel).

• Rubus chamaemorus (cloudberry).

• R. hispidus (bristly dewberry).

• Salix arctica (arctic willow).

• S. nivalis (snow willow).

• Smilax laurifolia (laurel greenbrier).

• S. walteri (coral greenbrier).

• Vaccinium cespitosum (dwarf bilberry).

• V. macrocarpon (large cranberry).

• V. oxycoccos (small cranberry).

• V. uliginosum (bog blueberry).

(The previous list was generated based on professional knowledge and a search in the USDA PLANTS database for obligate 

wetland [OBL] and facultative wetland [FACW] shrubs and 

subshrubs in the lower 48 States that grow less than 2 feet tall.)

Medium and tall woody shrubs (that typically grow taller 

than 0.5 meter high) and trees (other than seedlings) are not 

recorded in quadrats, but will be recorded along the line 

intercept and in the tree count. A low-stature shrub species 

would be recorded only in quadrats. A medium to tall shrub 

species would be recorded only in line intercept. This needs to 

be consistent to allow for interpretation of data collected at a 

site and for comparison with data collected at other sites. An 

individual shrub or tree may be recorded either in a quadrat or 

in the line intercept, but not in both.

Cover of tree seedlings less than 0.5 meters tall is recorded in 

the quadrats. A tree species could be in quadrats (because of 

seedlings) and in line intercept (because of tall individuals); 

therefore, in summaries the understory trees will need to be 

labeled as young/understory. 

In situations where there are many unusually small (less than 

0.5 meters) individuals (such as seedlings or browsed plants) 

of a woody species that typically grow taller than 0.5 meters, 

those small individuals could be recorded in the quadrats. This 

should be done only if sampling with line intercept would not 

accurately reflect the cover of that species.

The following guidance on cover estimation is from Manley et 

al. (2006, p. 10-6). “For each plant species, cover is estimated 

based on a vertically projected polygon described by the outline 

of each plant, ignoring any normal spaces occurring between 

the leaves of a plant. This best reflects the plant’s above- and 

below-ground zone of dominance. The only exception is for 

species represented by plants that are rooted in the quadrat, 

but have canopies that do not cover the quadrat or that are 

more than 1.8 m above the ground; cover for these species is 

estimated based on their basal area. Percent cover estimates are 

based on the current years’ growth, by including both living 

and dead material from the current year. Overlap of plants of 

the same species is ignored such that plants of the same species 

are grouped together into one cover estimate. Occasionally the 

canopy of different plant species overlaps; therefore, the total 

cover for a quadrat sometimes exceeded 100 percent. All trace 

cover estimates are recorded as 1 percent. The percent cover 

is recorded for the exact amount present at the time of the plot 

visit, and not adjusted (i.e., for immature or wilted plants) for 

the time of year during which the visit was made.”

Record the species, if possible. If the species cannot be determined (lack of flowers/fruits, herbivory, lack of expertise, etc.) 

then record the appropriate NRCS symbol or common name for 

the lifeform, some of which are listed in table 6 (the complete 

list is available online at http://plants.usda.gov/dl_unknown.html). 

It is useful to record something to distinguish the unknown 

species such as “dissected leaves” or “sessile spikes.”

Symbol Common name

2BRY Bryophyte (moss, liverwort, hornwort)

2FERN Fern or fern ally

2FORB Forb (herbaceous, not grass nor grasslike)

2FUNGI Fungus

2GRAM Graminoid (grass or grasslike)

2GL Grasslike (not a true grass)

2SHRUB Shrub (> 0.5m)

2SUBS Subshrub (< 0.5m)

2TB Tree, broadleaf

2TN Tree, needleleaf (coniferous)

2VH Vine, herbaceous

2VW Vine, woody

Table 6.—Lifeform symbols for unknown plants (subset of 

a larger list available on line at http://plants.usda.gov/ 

dl_unknown.html).
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 33

Use the comment field to distinguish different species within a 

lifeform category. For the unknowns, also collect a specimen, 

as described in the Plant Specimens section later in this guide. 

Recording cover of bryophytes (mosses, liverworts, and hornworts) can be beneficial and is recommended if there is time 

and expertise, but it is not required to record these nonvascular 

species. Bryophytes can be important components of wetlands 

in terms of their function and as indicators of condition. Sphagnum moss species in particular are reliable indicators of certain 

wetland conditions. If bryophytes species are not recorded, 

at least aggregate bryophyte cover will be recorded (see the 

following section). 

Bryophyte Cover 

Description—A measure of the abundance of byrophytes 

(mosses, liverworts, and hornworts). Bryophytes can be important components of wetlands in terms of ecosystem functioning 

and as indicators of condition.

How to measure and record—In each quadrat, record the 

total (aggregate) cover of all bryophytes—mosses (including 

Sphagnum), liverworts, and hornworts. A single value is 

recorded. No species names are recorded.

Ground Cover 

Description—This is a measure of the amount and types of 

physical cover at the ground surface. Ground cover can help 

protect the soil from erosion. Ground cover data can be used to 

monitor management activities and other disturbances that alter 

vegetation.

How to measure and record—In each quadrat, determine the 

ground cover at the four corners of the quadrat. Slide a pin flag 

along the inside corner of the quadrat frame and note what the 

pin touches when it reaches the ground surface or what it hits 

that is in direct contact with the ground, such as a rock or log 

(not something suspended over the ground). For each quadrat, 

record the quantity of hits (0 to 4) for each category. For each 

quadrat the total number of hits must add up to 4.

q Bare soil (soil particles < 2 millimeters).

q Gravel (2–75 millimeters).

q Cobble (75–250 millimeters).

q Stone (250–600 millimeters).

q Boulder (> 600 millimeters).

q Bedrock.

q Basal vegetation.

q Litter (leaf, needle litter, and other dead plant material or 

animal droppings).

q Bryophytes (mosses, hornworts, and liverworts).

q Water (with no other ground cover).

q Wood (recognizable as twigs, branches, or logs).

Line Intercept for Woody Cover

Description—This is a measure of the cover of woody 

vegetation (trees and shrubs) at the site. Woody cover provides 

information about successional status, wildlife habitat, vertical 

structure, and shading.

How to measure and record—Use a measuring tape along 

each transect to record the distance of canopy cover of trees 

and medium to tall shrubs (species that typically grow more 

than 0.5 meters tall). Shrub species recorded in line intercept 

should not have been recorded in quadrats (unless seedlings or 

browsed plants needed to be recorded). Tree species may be 

recorded in quadrats and in line intercept if seedling (quadrats) 

and overstory cover (line intercept) existed. Walk along the 

transect line and record the point on the tape (meters and one 

decimal) where the canopy of each species starts and ends (see 

figure 9 and table 7). Include gaps between leaves or branches as 

Figure 9.—Example of woody line intercept method with three 

shrub or tree individuals, each a different species. The arrows 

below the tape represent the length of each species that is 

recorded in table 7.

Table 7.—Data from the woody line intercept example in figure 9.

Species Start (m) End (m) Transect end

Acer rubrum 0 7.9

Viburnum edule 6.3 11.0

Populus tremuloides 9.1 14.2 16.0
34 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

part of the canopy distance. Ignore gaps of less than 25 centimeters 

between canopies of the same species. Do not distinguish the 

canopies of each individual of the same species; instead, 

continue the distance measure along the transect line until you 

are no longer under the canopy of that species. There can be 

overlapping species along the line intercept. Woody plants not 

rooted in the site, which hang over the site, would be included. 

Also record the distance where each transect ends.

Tree Diameter at Breast Height (DBH) 

and Density

Description—This is a measure of the number, size, and species 

of trees at the site, which allows density and other measures of 

abundance to be calculated for the site. Tree data are useful for 

characterizing the site as forested or not, which can be useful 

for categorizing sites. Tree data can be useful for understanding 

fire-related issues. Not all sites have the potential to support 

trees, so it is not necessarily an indicator of condition. 

How to measure and record—Trees are counted and measured 

within a 2-meter belt transect, extending 1 meter on each side 

of the line transect. Trees are considered to be species that 

typically grow large woody stems (described in the following 

paragraphs). Include all live and standing dead trees that have 

a DBH of 5 centimeters or greater, with breast height being 1.4 

meter above the ground. Count all trees that are entirely in the 

belt or that have the center of the trunk (bole) in the belt. For 

each individual tree, record the following information:

 Species. 

 DBH in centimeters. Measure with a DBH tape if possible.

 Distance along transect in meters and 1 decimal place.

 If it is alive or dead.

Trees—Trees are considered to be woody plants that generally 

have a single main stem and more or less definite crowns. In 

instances where lifeform cannot be determined, woody plants 

at least 5 meters in height at maturity will be considered trees 

(Brohman and Bryant 2005, adapted from the Federal Geographic 

Data Committee 1997). 

A source for determining the growth habit (tree, shrub, graminoid, etc.) of a species is the USDA PLANTS database: 

http://plants.usda.gov/index.html. 

Some species have multiple listings under growth habit, such 

as “Tree, Shrub” or “Tree, Vine, Shrub.” If the growth habit 

includes “tree,” they should be counted with this method. In 

data summaries, it may be desirable to separate or exclude certain 

species that seem less tree-like such as sagebrush, manzanita, 

and some willows that are listed as “Tree, Shrub” in the 

PLANTS database.

For more detailed guidance on tree data collection, see the 

Forest Inventory and Analysis field procedures at http://www.

fs.fed.us/rm/ogden/data-collection/pdf/iwfia_p2_50.pdf.

Additional Plant Species 

Description—This is a list of additional plant species observed 

at the site that were not detected by the other methods (quadrats, line intercept, etc.). This list includes species observed 

informally, as well as those observed during a systematic 

search of the GDE site. This is intended to supplement the list 

of species detected with the other methods and therefore to 

provide a more comprehensive list of species for the site. This 

is also a way to look for particular SOI. The search provides 

information on presence but does not provide a statistically 

sound measure of abundance. 

How to measure and record—Do a systematic walk in the 

following areas (see figure 10):

1. Between the existing transects (approximately halfway 

between transects, or between the transect and the GDE edge 

for the first and last transect).

2. Around the perimeter of the site.

While walking, look for and note plant species that were not 

recorded with the other sampling methods. This search is 

intended to cover different areas than the transects covered. All 

the areas could be searched, or a timed search could be done 

if there is not time to walk all the areas between transects and 

Figure 10.—Recommended search pattern for additional species.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 35

the perimeter. Indicate which type of search was done. If there 

is uncertainty about whether a species was recorded with the 

other methods, it is wise to record it in this Additional Plant 

Species list; it would be fine if a species appeared in this list 

and with the other methods.

In particular, look for threatened, endangered, sensitive, and 

invasive species (as defined by the region or States) and those 

species identified and described in the land management plan 

as management indicator or sensitive species, species of 

concern (SOC) or SOI, or focal species. It would be useful 

to have guides to help identify those species. 

Individual units within the Forest Service may want to track 

invasive species other than those on a State’s noxious weed 

list. For example, they may decide to include invasive species 

from adjoining States. The regional botany program lead is a 

good contact for information regarding invasive species lists. 

Forest Service personnel can download/export the invasive 

plant lists for any forest unit by using either (1) the Forest Service Plant List Wizard in I-Web or (2) the Geospatial Interface 

queries in ArcMap.

Note for Additional Plant Species search:

1. For very small sites, it is best to walk only the perimeter 

of the GDE, looking into the GDE, to avoid excessive 

trampling.

2. For small- to medium-sized sites, the systematic method 

described previously should work well (walking between 

transects and the perimeter).

3. For large sites, there might not be time to walk and search 

between each transect. An alternative for large sites is to do 

a timed search, such as for 30 or 60 minutes (note the time 

searched).

Plant Specimens 

Description—Plant specimens are useful for identifying 

unknown species, confirming species identifications, providing 

vouchers, and to help with training of future field technicians.

How to measure and record—A specimen should be collected for all unknown species. If it is not practical to collect 

specimens of all unknowns, then collect specimens for species 

with more than 5 percent cover in the quadrat. That will reduce 

the amount of work at a site, and it will generally result in 

only a minimal loss of information. This is because of the low 

cover of the species, and because in some cases those small, 

immature, or grazed specimens cannot be identified in the lab. 

Specific instructions for plant specimen collection are—

 Use the 1 in 20 rule as a guide: if fewer than 20 individuals 

are present at the site, do not collect the plant; instead, 

describe the plant, the setting, and take a photo.

 Collect as much of the plant as is reasonable, including—

§ Flowers or fruits. 

§ Belowground parts, to show whether it has a caudex, tap 

root, rhizomes, etc. Clean dirt from the roots. 

§ For woody plants, collect a portion of a branch with 

leaves and flowers/fruits/cones. 

§ Two pieces (stems or branches). 

 Complete a label (appendix 10) for each specimen with the 

following: Plant (or unknown number), collection number, 

date, site name, project/unit, collector, answers to questions 

about plant.

 Envelopes work well for small plants and seeds.

 Press the specimen in a plant press as soon as possible, with 

the label included. 

 Air out specimens so they do not get moldy. 

 List all collected specimens on a sheet or notebook.

 Make sure that any other data collectors at the site use the 

same unknown numbers for the same plants.

An experienced botanist should identify these specimens later, 

and that identification can be entered into the database in place 

of “unknown.”

To verify species identification and to facilitate training for future 

data collection, it is recommended that a few of the abundant 

species (based on visual observation) be collected at each site 

and then identified in the lab by an experienced botanist. It is 

also recommended that abundant bryophyte species be collected.

Genetic Information

Description—This is an optional method to collect genetic 

information about a species that is of interest to managers or 

researchers. This involves opportunistic collection of plant 

tissues for later deoxyribonucleic acid (DNA) analysis. 

How to measure and record—Crush plant tissues onto cards 

containing chemicals that arrest enzymatic processes and 

preserve DNA. Store cards in a cool, dry, dark, and secure 

environment; locking file cabinets in an air-conditioned space 

work well. Separate cards with sheets of clean paper, such 
36 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

as chromatography paper. Write the site ID on the cards and 

identify each sample with the full species name, the date of 

collection, and the collector’s name.

Targeted Plant Communities

Description—This is optional data collection for plant communities that were missed by the systematic transects/quadrats 

and that are considered important to describe for management.

How to measure and record—Establish a transect through the 

area of interest and collect data in quadrats at appropriate (and 

consistent) intervals along the transect. If it is a small area, you 

may only measure and record one quadrat. Use the same field 

form as is used for systematic quadrats, but cross out “Transect” 

and write “Targeted” and describe the location. Cross out 

“Distance” and write “Reason” and describe why the data are 

being collected (such as “to describe a pitcher plant community”). 

You may do this for multiple areas and communities within a 

site. These data should not be combined with systematically 

collected data in site summaries because that would create an 

inaccurate representation of species abundances.

Soil

Refer to the soils map to get an idea of the range of expected 

soils and whether the mapped soils are consistent with the soils 

observed at the site. 

These soil sampling methods are generalized from USDA NRCS 

(2006) and Schoeneberger et al. (2002) and are intended to give 

a general characterization of the soils and focus mainly on the 

level and duration of saturation. Information on the soil profile 

gives an indication of the amount of peat development and peat 

texture, the degree of water table fluctuation, and some indication 

of the underlying aquifer materials. This field guide is not intended 

for soil mapping purposes or to generate rigorous characterizations of soil profiles for the entire wetland site. Their precision 

will be such that they will be sensitive only to large changes 

in soil characteristics. Methods here should not be used when 

regulatory or jurisdictional requirements must be met.

Soil information is collected from holes along transects to 

describe the soil of the GDE site. There are various ways to 

take soil samples, such as with a soil shovel (sharpshooter), an 

auger (to extract a core), or a soil push probe. A technique that 

minimizes disturbances is recommended. If an auger is used, 

soil texture should influence the size of auger to be used. Water 

table elevations may also be recorded in the soil holes and 

these locations would also be logical locations for piezometers 

or minipiezometers should long-term water table monitoring 

be necessary (see Hydrology section). The depth of the soil 

sample should be about 50 centimeters to 1 meter, if possible. 

Advancement of the hole can stop when a total of 40 centimeters of organic soil is measured. 

Wet soils and standing water are more difficult for soil sampling, 

but in many instances, it can be accomplished if the water is not 

too deep. Sampling soils at springs is not necessary if only a mineral 

substrate exists; however, if organic soil exists at a spring, then 

soil information should be recorded. The following list describes 

some reasons why soil information might not be collected:

 Small site, where sampling is considered too destructive. 

 Threatened, endangered, or sensitive plant or animal species 

present at the site.

 Gravel, cobble, or boulder substrate.

 Deep water.

 Frozen ground.

An Equipment List for soil data collection is in appendix 6.

Where To Sample Soil

Soils data will generally be collected along each transect; 

however, if that is considered excessive, then soil sampling 

could be done at every other transect or every third transect. 

The locations of the soil samples will be at set distances along 

each transect using the following approach:

q Transect 1—50 percent.

q Transect 2—20 percent.

q Transect 3—65 percent.

q Transect 4—35 percent.

q Transect 5—80 percent.

If more than five transects exist, then repeat the sequence.

Locate soil holes at a set distance from the transect to avoid 

interference with vegetation sampling. In large sites, the soil 

hole could be 2 meters from the transect. In medium-sized sites, 

the hole could be 1 meter from the transect. At small sites, if 

soil sampling is done, the hole could be located on the transect, 

but should be dug only after the quadrat sampling is complete. 

If the soil holes are located a set distance from the transect, 

then, for the sake of consistency, always place them in the same 

direction from the transect; the direction closest to north is 

recommended. If the location of the soil sample lands where an 

obstacle such as a tree trunk or woody roots exists, then move 

1 meter forward along the transect, then 1 meter back, then 2 

meters forward, etc., until no obstacle exists.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 37

It is useful to mark the location of soil holes with a pin flag 

that is a different color than the flags used for the vegetation 

quadrats. Soil flags will help with relocation of the soil hole for 

the following purposes: to determine water table elevation after 

water level in hole stabilizes, to indicate where to take a photo, 

to help with the site sketch, and to fill in the hole when the field 

work is completed.

Toward the end of the site visit, “extra” soil data can be collected at targeted locations if there is a desire to learn more 

about particular features at the site.

Location of Soil Sample 

Description—This is the location within the site where soil 

information is collected, such as at set distances along the transects or specifically chosen points. Knowing how the location 

of a soil sample was determined helps with data interpretation. 

If the locations were systematically or randomly selected, then 

they can represent the entire site, although the accuracy will 

depend on the number of samples (more samples means a more 

accurate representation). If the locations were not selected 

in a systematic or random manner, but instead were selected 

because of some feature on the ground, then the data should 

not be used to represent the site. This location information is 

also important for repeat sampling, because locating samples 

with the same method (not necessarily the exact same spot) 

makes comparisons over time valid.

How to measure and record—

Unbiased—

 Use set distances along transects (as recommended previously).

 Select a randomly chosen point along transects.

 Determine center of site.

Targeted—Explain in notes.

Method of Extracting Soil

Description—This is the method or tool used to extract and 

observe soil. When analyzing soil information for the site, this 

will provide the level of reliability in the data collection effort.

How to measure and record—Record one of the following 

for each hole or core:

 Core/auger.

 Push probe.

 Shovel. 

 Other: _________.

Depth of Peat or Muck 

Description—Organic soils develop under saturated (waterlogged) conditions that prevent decomposition. Histosols, histic 

epipedon, and the presence of fibric soil material (peat), hemic 

soil material (mucky peat), and sapric soil material (muck) are 

considered the maximum expression of anaerobiosis and are 

interpreted as indicators of extremely long-term saturation. 

Organic soil materials have organic carbon content (by weight) 

of 12 to 18 percent or more, depending on the clay content of 

the soil. Laboratory analysis of organic carbon content can be 

done if needed to respond to specific management questions.

How to measure and record—Record the depth where the 

peat, mucky peat, and muck layers begin and end in the first 80 

centimeters. The definitions for the different organic layers to 

record are listed below:

1. Peat (fibric)—Undecomposed or weakly decomposed organic 

material; plant remains are distinct and identifiable; yields 

clear to weakly turbid water; no peat escapes between fingers. 

2. Mucky peat (hemic)—Moderately to well-decomposed 

organic material; plant remains recognizable but may be 

rather indistinct and difficult to identify; yields strongly 

turbid to muddy water; amount of peat escaping between 

fingers ranges from none up to one-third; residue is pasty. 

3. Muck (sapric)—Strongly to completely decomposed organic 

material; plant remains indistinct to unrecognizable; amounts 

ranging from about one-half to all escape between fingers; 

any residue is almost entirely resistant remains, such as root 

fibers and wood.

Depth to the Mineral Layer

Description—This is a measure of the depth to the first 

dominantly mineral layer below any organic layer that may be 

present. If there exists a significant organic layer, such as peat, 

then the mineral layer would be below that. If there is a small or 

nonexistent organic layer, then this depth will be shallow.

How to measure and record—Measure the depth from the 

surface to the first mineral layer (would be zero if no organic 

layer exists).

Texture of Mineral Layer

Description—Texture describes the mineral particle sizes and 

proportions in a sediment, such as clay, silt, and sand.

How to measure and record—Conduct a tactile evaluation of 

the soil texture of the first underlying mineral layer.
38 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Color of Mineral Layer 

Description—Color is useful to understand the composition 

of the soil and gives clues about the conditions the soil is 

subjected to.

How to measure and record—Describe the color of the first 

underlying mineral layer, using the Munsell color system chart.

Redoximorphic Features

Description—The type and location of redoximorphic features 

within the soil profile are used to interpret the degree of water 

saturation. Redoximorphic features, a result of iron (Fe) and 

manganese (Mn) oxidation and reduction, are not expected in 

organic soils, thus, there is no need to record redoximorphic 

features in histosols (40 centimeters or more of the upper 

80 centimeters is organic soil); mineral soils having a histic 

epipedon (surface horizons of 20 centimeters or more thick of 

organic soil material and underlain by mineral soil material 

with a chroma of 2 or less); or mineral soils having peat, mucky 

peat, muck, or a mucky modified soil texture within 12 inches 

of the surface.

For all other soils, redoximorphic features can indicate the 

duration of saturation. Under long duration (many weeks to 

months) of water saturation and reduction, Fe oxide depletion 

features occupy the entire groundmass. The Fe oxide-depleted 

groundmass appears greyer or lighter in color. Short duration 

of water saturation or rapid fluctuation of water tables results in 

Fe/Mn oxide nodules and coatings.

How to measure and record—Record the presence and depth 

of the following features:

 Redoximorphic concentrations—Redox concentrations 

include soft masses, pore linings, nodules, and concretions 

(see glossary for definitions). 

 Redoximorphic depletions—Bodies of low chroma (2 or 

less) having value of 4 or more where Fe/Mn oxides have 

been stripped or where both Fe/Mn oxides and clay have 

been stripped, see glossary for definitions. Soils having an 

abundance of gleyed material are saturated for long duration 

resulting in thorough reduction of iron to Fe+2 (ferrous 

iron). It is the presence of ferrous iron that is responsible for 

the greenish colors of gley. An absence of iron concentrations within a gleyed zone indicates a stable reducing 

environment and that periodic, or seasonal, fluctuation of 

soil saturation does not occur at that depth.

 Reduced matrices—A soil matrix that has low chroma and 

high value, but in which the color changes in hue or chroma 

when the soil is exposed to air. The color change should 

occur within 30 minutes.

 Presence of bog iron—A large-scale redoximorphic feature 

observed in areas where groundwater rich in reduced Fe 

moves to a more oxidizing environment.

Note: In soils derived from dark parent materials (value 4 or 

less, chroma 2 or less), redoximorphic features may be difficult 

if not impossible to recognize in the field.

Hydrogen Sulfide Odor

Description—A “rotten-egg” smell indicates that sulfate is 

being reduced, and, therefore, the soil is anaerobic. In most 

hydric soils, the hydrogen sulfide odor occurs only when the 

soil is saturated and anaerobic.

How to measure and record—Record whether or not the odor 

is detected as the hole is dug and the soil is removed.

Reaction To Dilute HCL

Description—A carbonate reaction can help identify systems 

supported by calcareous aquifers. This is a measure that is useful for identifying rich fens.

How to measure and record—Acid is applied directly to the 

soil specimen. A positive reaction confirms the presence of 

carbonates. The carbonates may be primary, secondary, or both. 

Carbonates including dolomite in soil can be inherited from 

parent material and occur in the fraction less than 2 millimeters in size. The specimen can be placed in a spot plate and 

given time (1 to 2 minutes) to react. Dolomitic carbonates 

react slowly; the reaction can be easily overlooked. Carbonates 

may occur in specific locations, such as along faces of peds. A 

number of specimens and locations should be tested. Dolomitic 

carbonates or specimens with a low content of carbonates may 

be more easily recognized with acid concentrations greater than 

1 meter.

Depth of Hole

Description—This is the maximum depth of the hole that was 

dug for soils data collection.

How to measure and record—Measure the depth of the pit or 

borehole from the surface to the bottom of the hole.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 39

Classifying Organic Soils

The “Keys to Soil Taxonomy” (USDA NRCS 2010) requires that histosols have organic soil materials that meet one or more of the following:

1. Overlie cindery, fragmental, or pumiceous materials and/or fill their

interstices and directly below these materials have a densic, lithic, or

paralithic contact.

2. When added with the underlying cindery, fragmental, or pumiceous

materials, total 40 centimeters (cm) or more between the soil

surface and a depth of 50 cm.

3. Constitute two-thirds or more of the total thickness of the soil to a

densic, lithic, or paralithic contact and have no mineral horizons or

have mineral horizons with a total thickness of 10 cm or less.

4. Are saturated with water for 30 days or more per year in normal

years (or are artificially drained), have an upper boundary within 40

cm of the soil surface, and have a total thickness of either—

a. 60 cm or more if three-fourths or more of their volume consists of

moss fibers or if their bulk density, moist, is less than 0.1 g/cm3.

b. 40 cm or more if they consist either of sapric or hemic materials,

or of fibric materials with less than three-fourths (by volume)

moss fibers and a bulk density, moist, of 0.1 g/cm3 or more.

5.	 Are 80 percent or more, by volume, from the soil surface to a depth

of 50 cm or to a glacic layer or a densic, lithic, or paralithic contact,

whichever is shallowest.

The “Keys to Soil Taxonomy” (USDA NRCS 2010) defines a histic 

epipedon as a layer (one or more horizons) that is characterized by

saturation (for 30 days or more, cumulative) and reduction for some

time during normal years (or is artificially drained) and either:

1. 	Consists of organic soil material that—

a.	 Is 20 to 60 cm thick and either contains 75 percent or more (by

volume) Sphagnum fibers or has a bulk density, moist, of less

than 0.1.

b.	 Is 20 to 40 cm thick.

2.	 Is an Ap horizon that, when mixed to a depth of 25 cm, has an

organic-carbon content (by weight) of—

a.	 16 percent or more if the mineral fraction contains 60 percent or

more clay.

b.	 8 percent or more if the mineral fraction contains no clay.

c.	 8 + (clay percentage divided by 7.5) percent or more if the

mineral fraction contains less than 60 percent clay.

Most histic epipedons consist of organic soil material. Item 2 provides

for a histic epipedon that is an Ap horizon consisting of mineral soil

material. A histic epipedon consisting of mineral soil material can also

be part of a mollic or umbric epipedon.

Box 4

Fen Characteristics

Description—This is a search for areas with fen characteristics 

within the site. Fens are groundwater-influenced peatlands with 

high water tables. The consistently high water table creates 

anaerobic conditions that slow decomposition, which leads to 

the development of peat or muck, which is plant material in 

various stages of decomposition (Mitsch and Gosselink 2007).

For the purposes of this field guide, we are first looking for 

areas with accumulations of peat or muck (supported by 

groundwater), which we call “fen characteristics,” and secondarily whether the soil meets the U.S. Fish and Wildlife Service 

(1999) definition of a fen. 

In some areas of the United States, fens have special designation and protection (USFWS 1999), and the Forest Service 

may wish to categorize wetlands as fen or nonfen wetlands. 

Common criteria and the U.S. Fish and Wildlife Service (1999) 

definition used to classify a wetland as a fen are (1) the wetland 

is primarily supported by groundwater, and (2) the wetland 

has organic soils meeting the USDA NRCS (2010) definition 

of a histosol or a histic epipedon in at least some part of the 

contiguous wetland (see box 4). USDA NRCS (2010) also states 

the following: “It is a general rule that a soil is classified as an 

organic soil (histosol or histel) if more than one-half of the upper 80 centimeters (32 inches) of the soil is organic or if organic 

soil material of any thickness rests on rock or on fragmental 

material having interstices filled with organic materials.”

How to measure and record—If a fen (groundwaterinfluenced peatland) was encountered during the systematic 

sampling, then record “yes” to the following fen characteristics 

question and use the soils data to determine if it meets the U.S. 

Fish and Wildlife Service (1999) definition of a fen; no further 

searching is necessary. 

If fen characteristics have not been observed during the site 

visit, then do a fen search in the same manner as the Additional 

Plant Species search described in the Vegetation section. The 

objective is not to find all fen areas at the site, but to determine 

if any fen areas exist at the site. While doing the search, pay 

particular attention to the wettest areas, where groundwater is at 

or near the surface for extended periods. Specific characteristics 

sometimes (but not always) associated with fens are—

 Wet or soggy conditions.

 Abundant mosses. 

 Soft or spongy surface that bounces or shakes when walked on.
40 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

 Herbaceous vegetation of obligate wetland species (defined 

in the Glossary under “wetland indicator status”).

§ A list of fen indicator species or “peat forming” species 

would be helpful, but they do not exist for all areas. One 

example of a fen indicator species list for California 

(Region 5) is in appendix B of Weixelman and Cooper 

(2009).

 Pattern of string and flark microtopography (hummock 

ridges and hollows).

If some of the previous characteristics are encountered in a 

particular area of a site, then evaluate the soil in that area as 

a target site (using methods described in this Soils section) to 

look for peat or muck. Record whether or not fen characteristics were observed. 

Yes, fen characteristics were observed at the site, which 

include—

 Groundwater influenced.

 High water table.

 Peat or muck present.

No, fen characteristics were not observed at the site:

 In addition to the absence of the previous characteristics 

of fens, other clues indicating that it is probably not a fen 

include redoximorphic features or rock (cobble or larger) 

on ground surface. Areas influenced by beaver activity may 

appear like a fen, but may not actually be a fen.

Also, answer whether the site has soil that meets the USDA 

NRCS (2010) definitions of a histosol or histic epipedon:

 Yes, histosol or histic epipedon observed at the site.

 No, histosol or histic epipedon not observed at the site.

Hydrology

An Equipment List for hydrologic data collection is in 

appendix 6.

Water Table

In general, water table measurements will be done at wetlands 

and not at springs, although there are exceptions. Water table 

data will be collected at one point along each transect (described 

in the Transect Layout section). These data can be collected in 

the boreholes created during soil sampling, which are established 

at set distances along each transect. 

Note: One-time water table measurements give only a general 

idea of the water table for a site. Multiple measurements during 

the season using piezometers would provide information about 

the variability (or seasonality) of the water table. Methods to 

collect more detailed groundwater data are described in separate 

technical notes, which can be found on the Minerals and Geology 

page on the Forest Service Web site: http://www.fs.fed.us/geology.

 Groundwater Monitoring Well Installation in Wetlands. 

 Groundwater Level Measurements.

 Analysis of Groundwater Level Data.

Location of Water Table Measurements

Description—The location within a wetland where a water 

table depth measurement is taken will generally be at set 

distances along the transects, but it could also be at targeted 

locations. In general, wells or piezometers are required for 

meaningful, long-term water table monitoring.

Knowing how the water table sampling locations were determined is important for data interpretation. If the locations were 

systematically or randomly selected, then they can represent the 

entire site, although the accuracy will depend on the number of 

samples (more samples means a more accurate representation). 

If the locations were not selected in a systematic or random 

manner, but instead were selected for some specific reason, 

then the data should not be used to represent the site. This location information is also important for repeat sampling, because 

locating samples with the same method (not necessarily the 

exact same spot) makes comparisons over time valid.

How to measure and record—Establish locations with one of 

these methods.

 Systematic distance along transects (as recommended previously); note the transect number and distance along transect.

 Randomly chosen point along transects.

 Center of site.

 Other: __________. 

Source of Water Table Measurements

Description—This indicates the source of the water table depth 

measurement or where it was taken in a wetland. This helps 

with interpreting the water table data.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 41

How to measure and record—If wells are installed, the water 

table measurements should be taken from the wells rather 

than from the soil core boreholes. Note which of the following 

sources was used:

 Soil core borehole.

 Depression. 

 Well/piezometer.

 Other: __________.

Hole Depth

Description—This is the maximum depth of the hole where 

the water table data are collected. If the soil hole is used, then 

this will be the same value entered for the soil hole depth.

How to measure and record—Measure the depth of the pit or 

borehole from the surface to the bottom of the hole.

Water Table Depth

Description—This attribute helps to establish the depth to water below the ground surface in wetlands. It would probably not 

be measured at springs that do not have an associated wetland, 

because the water table or piezometric surface at a spring is by 

definition at the surface.

This attribute helps provide an understanding of conditions 

that influence plant species, particularly wetland plant species 

that are highly dependent on a shallow water table for survival. 

Small changes in water table depth can cause changes in 

wetland plant community composition.

How to measure and record—Groundwater depth (centimeters) is measured in the borehole from the soil core or by 

augering a hole. The appropriate depth of a hole is somewhat 

site specific, but would typically be a 0.5 to 1 meter or to the 

bottom of the peat (where applicable). Be aware that once the 

hole penetrates below the bottom of a peat layer, the water 

level may rise in the borehole, indicating artesian conditions. 

Peat layers are occasionally confining units and can sometimes 

“float” on the underlying aquifer. Therefore, in those situations, the water level measured in a hole would represent the 

piezometric surface of the hydrogeologic unit underlying the 

peat, which frequently exhibit strong upward vertical hydraulic 

gradients. To get the true water table elevation within the peat, 

the borehole must not penetrate through the base of the peat.

Before measuring water table depth, allow time for water in 

holes to equilibrate (at least 30 minutes, but preferably a few 

hours). Water table measurement could be taken just prior to 

refilling the boreholes at the end of the field day, which would 

provide time for the water in the hole to equilibrate with the 

water table. 

If water is at or above the surface, then it is not necessary to 

auger a hole or measure water table depth. The water table 

would be at the surface or at a depth of zero.

Steps to measure water table depth:

1. Auger a hole approximately 0.5 to 1 meter in depth. A hole 

can also be dug using a sharpshooter shovel although this 

creates more disturbance to the wetland. 

2. Allow the water level in the hole to equilibrate. Monitor 

the water level depth to determine when the water level has 

stabilized.

3. Lay a shovel or similar object across the top of the soil pit 

opening and measure from the bottom of this object. Record 

the distance to water. 

4. For standing water, record zero, which indicates the water is 

at or above the ground surface.

If no water remains in the hole, even after waiting for a period 

of time, then record it as “dry.”

Water Table Type

Description—This describes the type of water table that exists 

at the site based on observations made while measuring the 

water table depth. This information gives insight into the vertical gradients in the underlying aquifer.

How to measure and record—Choose the term that best 

describes this site, based on the water table measurements taken 

previously:

 Apparent—Water level stabilized in a fresh unlined borehole.

 Artesian—The static level within a cased borehole where 

water rises above an impermeable layer (e.g., peat layer) 

due to a positive hydrostatic head or where water discharges 

from an unlined borehole.

 Ponding—Standing water on top of the soil.

 Unknown.

 Other: __________.
42 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Flow

Flow Patterns for Site

Description—This indicates whether the inflow and outflow 

are surface water, groundwater, or a combination of the two. 

This helps to characterize the overall water budget of the wetland. The water budget of wetlands varies in the dependence on 

groundwater inflow/outflow or surface water inflow/outflow. 

How to measure and record—

Inflow (select one):

 Dominated by groundwater inflow.

 Dominated by surface water inflow and/or precipitation.

 Substantial amounts of both groundwater and surface water 

inflow.

Outflow (select one):

 Dominated by groundwater outflow.

 Dominated by surface water outflow.

 Substantial amounts of both groundwater and surface water 

outflow.

 Dominated by evapotranspiration.

Occurrence of Surface Water

Describe the occurrence of surface water at the site using one 

of the following categories (may select multiple):

 No standing or flowing water visible.

 Patches of standing water.

 Extensive standing water.

 Flowing water in channels.

Flow Instrument

Record the name of the instrument used to measure flow (or 

discharge). The instrument will vary depending on the site 

type; therefore, multiple options are presented in appendix 11.

Flow Method

Record the method used to measure flow (or discharge). The 

method will vary depending on the site type; therefore, multiple 

options are presented in appendix 11.

Flow Rate

Description—This is a measure of the discharge from the aquifer 

to the surface. This attribute is more important for springs than 

wetlands supplied by diffuse discharge. The flow of a spring 

is important for both ecological reasons and human uses of the 

spring water. In many cases, the flow of a spring correlates with 

the ecological functions and values of the spring habitat.

Where to measure flow—If measuring a single channel, measure discharge as close as possible to the spring source. In some 

situations, there will not be a single distinct channel where flow 

can be measured, in which case follow these guidelines:

 If there are multiple channels, and if they all converge to a 

single channel, measure discharge in the single channel as 

close as possible to the confluence of all of the multiple channels.

 If there are multiple channels that do not converge, then 

measure flow in as many channels as possible. Record each 

measure with an explanation that it is different (completely 

or partially) than other measures of flow at the site.

 For hanging gardens and wet walls, if possible, take a flow 

measurement at the base of the wall where flow coalesces 

into a channel. If this is not possible, photo documentation 

of the wetted area of rock face is an option.

 If flow is very diffuse (as in a sloped wetland or seep), then 

flow measurements may not be possible.

How to measure and record—Flow measurement applies 

mainly to springs, but can be applied to wetlands that have 

flowing water, such as in an inflow, an outflow, or distinct 

channels.

Measure the quantity of water discharging from the GDE with 

one of the methods listed in appendix 11, which also describes 

the measurement methods. Flow should be measured and recorded 

multiple times (three is recommended) at the same location 

to increase accuracy. Multiple measures at different locations 

might also be necessary to capture the totality of flow. Record 

and store all flow measurements (in the field and in the database) 

to allow for accurate analysis of flow for the site. 

Also, record an estimate of the percent of the surface discharge 

that was captured. 

For limnocrenes that do not have outflow, the static head change 

method is used. For limnocrenes that have an outflow, use one 

of the other measurement techniques described previously. 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 43

If flow was not measured, then explain why, by selecting one 

of these options:

q Diffuse outflow.

q No outflow.

q Not a spring.

q Spring is dry.

q Other: __________.

Note: It may be difficult to estimate the discharge of springs 

and wetlands that (1) are small, (2) have water that is shallow 

and broadly or unevenly spread over a wide area, or (3) have 

limited moving water. Discharge often changes throughout the 

day (because of evapotranspiration), seasonally, or annually, 

which decreases the effectiveness of single measurements to 

precisely quantify long-term discharge characteristics. Highly 

quantitative discharge measurement would be a component of 

a Level III survey. 

Record notes on flow—Make notes on evidence of recent high 

discharges, such as high water marks, oriented vegetation, or 

debris on or above the channel or floodplain.

Spring Channel Characteristics

For sites that have spring brooks or outflow channels, record 

information for the following questions.

Hydroperiod 

Description—This describes the temporal flow characteristics 

of a spring. This information is valuable for assessing the 

importance of the spring for habitat for aquatic organisms. 

Perennial springs are frequently of higher value for aquatic and 

terrestrial species than are ephemeral springs.

How to measure and record—Estimate the hydroperiod of 

the spring by selecting one of the opions below. If the field visit 

takes place in the dry season and the spring is flowing, it is 

likely perennial.

q Perennial (must have continuous flow at time of visit).

q Intermittent (visible evidence of flow, known to flow at 

certain times of the year).

q Not determined.

Length of Outflow Stream

Description—This is an estimate of the length of the spring 

brook up to a maximum of 20 meters downgradient. Twenty 

meters is an arbitrary cut-off that has been established because 

at some distance downstream, the spring brook changes from a 

spring-specific habitat to a lotic habitat because of cumulative 

changes in flow, temperature, and water quality. The spring 

brook serves as a habitat for many spring-specific species 

(crenobiontic species), so its length is of interest for understanding aquatic biology. 

How to measure and record—Record the distance of the spring 

brook to the downstream limit of surface flow from (1) the source 

(orifice) of a spring (that does not have a wetland between the 

spring and the outflow channel), (2) the point where water coalesces into a channel for diffuse springs and discharge wetlands, 

(3) the outflow from a limnocrene, or (4) the downgradient edge 

of a wetland:

q < 5 meters

q 5 to 10 meters

q 10 to 15 meters

q 15 to 20 meters

q > 20 meters

What Happens to Stream Outflow

Description—This is a general description of what happens to 

the spring brook or stream downstream of the sampling area.

How to measure and record—If flow continues beyond 20 

meters (downstream of the site), then also note what happens to 

the flow after the 20 meters, using the following options: 

 Disappears into the ground.

 Continues as far as can be seen.

 Flows into another stream.

 Some flow is diverted. 

 Becomes intermittent.

 Other: __________.

Detailed Spring Brook Measurements

It might be useful to collect detailed data on spring brook characteristics to evaluate or monitor habitat for spring-dependent 

species or for other purposes. Those data could include channel 

dimensions, substrate particle size distribution, streambank 

characteristics, and others. If such stream data are desired, then 

various protocols can be used, including the following:

 PACFISH/INFISH Biological Opinion Effectiveness Monitoring for Streams and Riparian Areas (USDA Forest Service 

and USDI Bureau of Land Management) http://www.fs.fed.us/ 

biology/fishecology/new.html#pibo_reports.

 Sada and Pohlmann (2006 draft), Level 2 inventory.
44 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Water Quality

Some core field-derived water quality parameters are included 

to help characterize the site. These are the following: temperature, specific conductance, pH, and either oxidation/reduction 

potential (ORP) or dissolved oxygen (DO). In addition, water 

samples may be collected for laboratory analysis of a wider 

range of water quality parameters, if they are needed to address 

the management requirements for the field guide implementation. 

Detailed instructions for collecting water samples from wells 

and surface waters and analyzing those samples, along with 

quality assurance/quality control procedures can be found 

in the USGS National Field Manual for the Collection of 

Water-Quality Data (National Field Manual). The National 

Field Manual provides guidelines and standard procedures for 

USGS and other Government agency personnel who collect 

samples used to assess the quality of the Nation’s surface-water 

and groundwater resources. Each chapter of the National Field 

Manual is published separately and revised periodically. Newly 

published and revised chapters are posted on the USGS Web 

page “National Field Manual for the Collection of WaterQuality Data,” http://water.usgs.gov/owq/FieldManual/.

If there are wells, the water quality samples should be taken 

from the wells with a bailer or pump. For springs or discharge 

areas within wetlands, water quality measurements should always be taken at the source. Water in wetlands may be ponded 

or flowing. In either case, targeted samples should be collected 

from an area that has sufficient depth, is within the wetland, 

and away from inlets (natural or anthropogenic) because 

inlets may influence the composition of the water sample. In 

summary, water quality sampling should be done at one of the 

following locations, which are listed in order of preference:

 Wells in wetlands (if present) and at the source (orifice) of 

springs. 

 Where flowing water exists in wetlands.

 Standing surface water. 

 Holes created by the soil sampling.

§ Time is needed for water to equilibrate.

§ Temperature may be the only attribute that can be accurately measured in a borehole because the other water 

quality attributes (conductivity, pH, DO, and/or ORP) 

may be affected by the digging process. 

Location of Water Quality Measurements

Description—The location within a wetland or spring where a 

water sample or measurement is collected is either an unbiased 

location or a targeted location. Knowing how the water quality 

sampling locations were determined is important for data interpretation. If the locations were unbiased (such as systematically 

or randomly selected locations), then they can represent the 

entire site, although the accuracy will depend on the number of 

samples (more samples means a more accurate representation). 

If the locations were not selected in a systematic or random 

manner, but instead were selected for some specific reason 

(targeted), then the data should not be used to represent the 

entire site. This location information is also important for repeat sampling, because locating samples with the same method 

makes comparisons over time valid. 

How to measure and record—Surface water quality sampling 

should be completed before collecting data for other indicators 

to avoid degrading the water while completing other sampling 

tasks. Use flagging if necessary to keep crew members clear of 

the water sampling location until the water has been sampled. 

The location of the water quality measurement is either a 

systematically located soil hole or a targeted location:

 Unbiased—

§ Transect and distance (soil hole).

§ Randomly chosen point.

§ Center of site.

 Targeted location—

§ Spring source (recommended for springs).

§ Downgradient from spring source.

§ Stream exiting wetland.

§ Standing water (includes pools).

§ Hole (dug or augered; other than systematic soil sample 

hole).

§ Well/piezometer. 

§ Other: __________.

Time of Water Quality Measurements

Description—This is the time of day that the sample or 

measurement was collected. This information will help with 

the interpretation of the data because many water quality 

parameters fluctuate diurnally because of temperature changes, 

evapotranspiration, and photosynthesis. 

How to measure and record—Record the time of day that the 

sample or measurement was taken.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 45

Temperature of Water

Description—This is the temperature of the groundwater discharging at the spring or wetland. Water temperature is an important factor structuring aquatic communities, and it may give 

insight into the source of the groundwater. The temperature of 

water discharging from a spring is particularly meaningful. The 

temperature of water discharging to the surface of a wetland 

is not an accurate measure of groundwater temperature, but it 

provides general evidence about the temperature of the groundwater. Extreme temperature values might be an indication that 

more careful work is needed.

How to measure and record—One way to measure water 

temperature is with an electronic device that also measures dissolved oxygen or conductivity. Calibration is not necessary for 

temperature measurements using a high-quality device. Record 

in degrees Celsius. Expected ranges of values are 4 to 60 

degrees Celsius. For springs unaffected by geothermal heating, 

the water temperature is generally close to the average annual 

temperature of the recharge area.

Water pH

Description—pH is the measure of hydrogen ion activity, 

which indicates the acidity or alkalinity of water. It is measured 

on a scale from 0 to 14, with a pH of 7 indicating neutral 

conditions. Smaller numbers indicate acidic conditions; larger 

numbers indicate basic conditions. The pH typically responds 

to hydrologic disturbance in wetlands; therefore, pH can be 

an indicator of disturbance. The pH is also important in classifying wetland sites (Cowardin et al. 1979) and defining rich 

and poor fens. Aquatic fauna and flora are also sensitive to pH 

conditions. The pH of rain is about 5.6, but can range from 5.6 

to about 4.5.

How to measure and record—Measure the pH of the water 

using a hand-held field meter. The meter should be kept clean, 

with fresh batteries, and calibrated at least daily, following the 

manufacture’s recommendation. The pH probes generally have 

a limited lifetime, and a backup probe should always be carried. 

A backup meter is highly recommended. Record in standard 

pH units. The expected range of pH values is 4.0 to 8.0.

Specific Conductance of Water

Description— Specific conductance (also called electrical 

conductance or conductivity) is the measure of the ability of an 

aqueous solution to carry an electrical current. This ability is 

dependent on the amount of dissolved ions in the solution, and 

is, therefore, an indicator of total dissolved solids in the solution. Conductivity provides insight into water sources, and it is 

an indicator of conditions important to aquatic life because of 

requirements to maintain osmoregulatory balance. Conductivity 

typically responds to hydrologic disturbance in wetlands. 

Conductance is also important in classification of wetland sites 

(Cowardin et al. 1979).

How to measure and record—Measure conductivity using a 

field meter. The meter should be kept clean, with fresh batteries, and calibrated periodically following the manufacturer’s 

recommendation. Most high-quality meters do not require 

frequent calibration. Record in microsiemens/centimeter 

(mS/cm). Expected ranges of values are 10 to 5,000 mS/cm.

Oxidation-Reduction Potential or ORP 

(DO is an alternative)

Description—Oxidation-reduction (redox) reactions (reactions 

involving electron transfer) mediate the behavior of both inorganic 

and organic chemical constituents by affecting solubility, 

reactivity, and bioavailability. This data will help provide 

information about the biogeochemistry of wetlands, which is 

controlled largely by oxidation-reduction reactions. Expected 

values for Redox potential (also called Eh) range from -300 

millivolts (mVs) to +700 mV (see figure 11). Redox potential 

is significantly affected by the oxygen content of the soil and 

porewater. In oxidized systems where aerobic organisms function, 

the Eh range is very narrow, approximately +700 mV to about 

+300 mV. Below values of +300 mV, facultative anaerobes 

(primarily bacteria) function down to about 0 mV. Below this 

range, obligate anaerobes function. In wetland (waterlogged 

or flooded) soils, Eh can be anywhere along the entire scale. 

Where oxygen is present in wetland soil, the Eh can be as high 

as in a drained soil, but where oxygen is not present, Eh can be 

very low (-250 to -300 mV) (U.S. EPA 2008). The Eh-pH diagram 

in figure 12 can be used to interpret the ORP measurements. 

Figure 11.—Range of ORP values for wetlands.
46 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Figure 12.—Distribution of Eh-pH values in natural aqueous 

environments. Zone A is acidic mine drainage, B is rain, C is 

stream water, D is ocean water, E is groundwater, F is bog 

water, G is anaerobic wetlands (redrawn from Langmuir 1996 

and Baas-Becking et al. 1960).

saturation, while pure water at 25 degrees Celsius (77 degrees 

Fahrenheit) can hold only 8.4 mg/L at 100 percent saturation. 

Water with a high concentration of dissolved minerals cannot 

hold as much DO as pure water. 

How to measure and record—Measure DO using a field 

meter. The meter should be kept clean, with fresh batteries, and 

calibrated at least daily following the manufacture’s recommendation. If there are weather fronts moving through the area, 

it may be necessary to calibrate before each measurement. 

Record DO in mg/L. Expected ranges of values for DO are 0 to 

13 mg/L.

Aquatic and Terrestrial Fauna

This section summarizes Forest Service protocols developed 

for the inventory and monitoring of aquatic and terrestrial 

fauna that may be used in conjunction with this field guide. The 

protocols referenced can be found at http://www.fs.fed.us/emc/

rig/protocols/biodiversity.shtml.

It is recommended that Forest Service units use these published 

protocols whenever possible. Use of other protocols should be 

undertaken only when existing agency protocols do not meet 

the management requirements.

An excellent starting point for determining how to conduct 

aquatic and terrestrial observations is the “Multiple Species 

Inventory and Monitoring Technical Guide” by Manley et al. 

(2006), which has the following purpose:

The Multiple Species Inventory and Monitoring (MSIM) 

protocol is intended to serve as a consistent and efficient 

method for obtaining basic presence/absence data and associated habitat condition data for a large number of individual 

species at sites that represent a probabilistic sample (Manley 

et al. 2006, p. 1-1).

MSIM describes sampling methods to characterize a site, such 

as timed searches, sampling a defined area or a certain volume. 

This is important so that the same time or effort can be applied 

in future sampling of that site, allowing for the evaluation of 

trends. In addition, it may also be useful to scale the amount of 

time and effort to the size of the site so that different sites can 

be compared. For example, with the Aquatic Visual Encounter 

Surveys (AQVES), MSIM recommends that observers spend 

approximately 15 minutes per 20 linear meters sampled 

(with the clock stopped when extra time is needed to identify 

species, count individuals, or maneuver around obstacles). 

How to measure and record—Measure the ORP of the water 

using a hand-held field meter that has been calibrated using 

Zobell solution. ORP in water is measured in wells, springs, 

and standing or flowing water. The meter should be kept clean, 

with fresh batteries, and calibrated daily following the manufacturer’s recommendation. Record in mVs. 

Dissolved Oxygen or DO (alternative to ORP) 

Description—This is a measure of the amount of DO in the 

groundwater discharging at a spring or wetland. DO at a spring 

gives insight into the source of the groundwater discharging 

and the residence time in the aquifer. In a wetland, DO is a 

function of the biogeochemical processes taking place. 

Because fish and other aquatic organisms cannot survive without 

oxygen, DO is an important water quality parameter for surface 

water systems. Cold water holds more oxygen than warm water. 

Pure water at 4 degrees Celsius (40 degrees Fahrenheit) can 

hold about 13.2 milligrams per liter (mg/L) DO at 100 percent 

Note: Measured ORP values have to be converted to Eh to be 

able to use the Eh-pH diagram in figure 12. Converting ORP 

measurements to Eh depends on the type of ORP electrode 

used. The electrode manufacturer typically provides conversion 

factors for various temperatures.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 47

Another example is the timed search and the systematic pattern 

described in the Additional Plant Species search method in the 

previous Vegetation section. 

Data on species presence, and in some cases abundance, can 

be obtained by timed searches, capture/collection efforts, traps, 

or incidental observation. It is important to note how the data 

were obtained because that affects the ability to use the data to 

characterize faunal presence at the site.

Documentation of invasive species is an important part of 

GDE surveys. See the USGS Nonindigenous Aquatic Species 

Web site (http://nas.er.usgs.gov/) for lists and information on 

invasive vertebrates, invertebrates, and plants.

The following section presents categories of organisms and 

sampling techniques available (derived primarily from MSIM) 

to assess them. 

Note: Collecting or disturbing animals at small sites (such as 

springs) could have a detrimental effect on the local population—therefore, consider not collecting or disturbing fauna at 

very small sites.

Aquatic Vertebrates

Description—This attribute describes the presence and/or 

abundance of aquatic vertebrates, including birds, mammals, 

amphibians, reptiles, and possibly fish. Some springs and 

wetlands provide important habitats for aquatic vertebrates. If 

an inventory is taking place in an area with aquatic vertebrates 

of interest, this component can be added to the inventory work. 

How to measure and record—AQVES, as described in 

MSIM, can be used to detect all classes of aquatic vertebrates, 

including birds, mammals, amphibians, reptiles, and possibly 

fish (presence). 

This type of survey involves a timed search that systematically 

covers the site in a manner comparable to the Additional Plant 

Species search method in the previous Vegetation section. For 

each observation, the following data are recorded: species, 

number of individuals observed, life stage, and substrate.

Terrestrial Herpetofauna 

Description—The purpose of this attribute is to detect the 

presence of various types of terrestrial herpetofauna. Some 

springs and wetlands provide important habitat for terrestrial 

herpetofauna during a portion of their life cycle. If an inventory is taking place in an area with terrestrial herpetofauna of 

interest, this component can be added to the inventory work. 

How to measure and record—The Amphibian and Reptile 

Visual Encounter Survey described in MSIM (http://treesearch. 

fs.fed.us/pubs/24985) can be used to document terrestrial

herpetofauna. 

This type of survey involves a timed search that systematically 

covers the site. For each observation, the following data are recorded: observer, time, search, time elapsed, species, detection 

type (e.g., visual, auditory, capture, sign), age class of captures 

(juvenile, subadult, or adult), snout-vent length, substrate type 

(e.g., rock, log, bare ground), and location along the transect.

Terrestrial Vertebrates 

Description—The purpose of this attribute is to detect the 

presence of various types of terrestrial vertebrates. Some 

springs and wetlands provide important habitat components for 

terrestrial vertebrates. If an inventory is taking place in an area 

with terrestrial vertebrates of interest, this component can be 

added to the inventory work. 

How to measure and record—Terrestrial Visual Encounter 

Surveys can be used to record the presence of terrestrial species 

including land birds, and various-sized mammals, as well as all 

forms of vertebrate sign, as described in MSIM (http://

treesearch.fs.fed.us/pubs/24985). 

For this survey, observers walk along transects that are distributed across the site, for a set time, and record all animal signs 

(not amount) and presence of target animals (not numbers). In 

addition, observers note observer, time, search time elapsed, 

species, detection type (e.g., visual, auditory, capture, sign), 

age class of captures (juvenile, subadult, or adult), and substrate 

type (e.g., rock, log, bare ground).

Aquatic Macroinvertebrates

Description—Springs and wetlands can provide important 

habitat for aquatic macroinvertebrates, which can be important 

for management and restoration. Aquatic macroinvertebrates 

are useful bioindicators because some taxa are sensitive to 

disturbance while others are tolerant. Sampling aquatic macroinvertebrates can expand our knowledge about the ecology of 

these organisms; some spring invertebrates have yet to be discovered (Stout and Wallace 2003). Appendix 12 (Identification 

of Freshwater Invertebrates) provides representative drawings 

of groups of aquatic macroinvertebrates important in springs and 

other GDEs and a “Key to Macroinvertebrate Life in the River.”
48 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Objectives for collecting data on aquatic macroinvertebrates 

can vary, including the following:

 To compare composition among sites. 

 To assess baseline biodiversity.

 To evaluate aquatic habitat health or water quality.

 To search for SOC.

 To gain deeper ecological understanding.

How to measure and record—There are various approaches 

to collecting data on aquatic macroinvertebrates, some of which 

are presented in the following list (in descending order of detail 

and effort):

1.	Quantitative sampling—This approach involves rigorous 

sampling methods to quantify the types and abundance of 

macroinvertebrates, in a manner from which a statistical 

confidence of the estimate can be obtained (Merritt et al. 

2008). Quantitative sampling takes significant time and 

effort in training and fieldwork. This field guide does not 

include methods for quantitative sampling.

2.	Semiquantitative sampling—This is a systematic approach 

(approximate time or area known) to document the types of 

macroinvertebrates and some information about abundance 

(Merritt et al. 2008). Different habitats or geologic settings 

are sampled to accurately represent the site. This is not an 

effort to document all taxa present, but it provides information on the relative abundance of taxa encountered. 

3.	 Targeted search—This is a qualitative approach that seeks 

to find as many different types of macroinvertebrates as 

possible at the site. This involves searching the habitats 

where the macroinvertebrates would be expected to live. 

This generates a thorough list of species present, but it does 

not provide data about abundance. 

The type of sampling done will depend on the management 

requirements associated with the purpose for inventorying the 

site. If multiple approaches are used at a site, it is important that 

the data are distinguished according to the method of collection. 

Semiquantitative sampling will work well at sites with a developed 

stream channel with flow. The targeted search will work better 

if a stream channel does not exist. No matter what methods are 

used, the spring source should be sampled if one exists. 

Most published approaches to sampling aquatic macroinvertebrates are focused on stream systems. Protocols for spring and 

wetland systems are not as common, but the stream protocols 

can be modified for springs. Methods described in the following paragraphs are modifications of techniques developed by 

Sada and Pohlmann (2006) and Stevens et al. (2006). 

Methods for sampling aquatic macroinvertebrates in systems 

without flowing water (such as springs with no flow, fens, or 

other wetlands) are not well developed, although several States 

are developing methodologies for sampling aquatic invertebrates in wetlands (U.S. EPA 2002). In this field guide, we 

present adaptations for sampling with minimal or no flowing or 

standing water. 

Sampling at small sites, such as some springs, should be 

conducted in a manner that causes minimal disturbance, such as 

avoiding walking in the water (see “Note for very small sites” 

in the first part of this Field Survey Activities section). 

Regardless of method, invasive taxa in each region should be 

looked for and recorded. The USGS Nonindigenous Aquatic 

Species Web site (http://nas.er.usgs.gov/) has lists and information on invasive freshwater mollusks and crustaceans.

Aquatic invertebrate collection should be done after water 

quantity and quality variables are measured, to minimize effects on the results. 

Equipment (and techniques)

Equipment for semiquantitative and qualitative sampling for 

GDE macroinvertebrates is comparable to that used in lentic 

and lotic environments (e.g., Barbour et al. 1999). The small 

size of some springs will require modifications of equipment so 

that a relatively small proportion of those sites is disturbed (see 

table 8). 

Based on the conditions, use table 8 to determine what type of 

net to use for macroinvertebrate sampling. The techniques to 

collect samples are described in the paragraphs following the 

table.

Table 8.—Macroinvertebrate sampling techniques.

Conditions Net

Flowing water 5–50 cm deep Kick net

Flowing water 2–5 cm deep, dense aquatic

vegetation, standing water, pools, free-floating

invertebrates, vegetation, and sand

D-frame net

Narrow (<35 cm wide) and shallow (< 10 cm deep)

stream channels, standing water, pools, and freefloating invertebrates.

Hand net

(aquarium net)
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 49

Kick net—Submerge the kick net into the water perpendicular 

to the current, burrowing the pole ends into the sediment to stabilize. Make sure there is not a gap between the bottom of the 

net and the bottom substrate. Cross the poles above the surface. 

Use a pole, stick, or foot to disturb the area approximately 0.1 

square meter(1 square foot) upstream of the net for 1 minute. 

Gravel and cobble substrates should be rotated and scraped on 

all sides while being disturbed to remove invertebrates from 

the underside. Once the sample is collected, scoop up the kick 

net to avoid losing invertebrates. 

D-frame net—In flowing water, hold the net perpendicular to 

the current and stabilize in the sediments. The part of the net 

attached to the frame is canvas to prevent tearing. Disturb the 

sediment upstream from the net in an area approximately 0.1 

square meter(1 square foot) with a pole or foot. Use the same 

time intervals for disturbing sediment as discussed previously 

for the kick net. In open water, sweep the D-frame net through 

the water or aquatic vegetation, or dip it into the sand. The 

sand samples should be transferred to a white pan and searched 

for invertebrates. The D-frame can also be used in vegetation 

where little or no water exists.

Hand net (aquarium net)—Use the same techniques 

described previously for the D-frame net. For spot sampling, 

a hand-net is used to sweep up free-floating invertebrates and 

those on the water surface. 

Semiquantitative Sampling

Springs—For springs, the area sampled will be the spring 

runout channel from the spring source to a point 20 meters 

downstream (or the farthest downstream point if less than 20 

meters). Begin the survey at the downstream end to minimize 

disturbance to the other samples. End the sampling at the 

spring source. After each sample is collected, generate a 

random number between 2 and 6 (see appendix 9) and move 

upstream that number of meters and sample at that location. 

If a sampling location is hard or unsafe to access, move to 

the closest accessible sampling location. The final sample is 

always conducted at the spring source because of the higher 

probability of encountering unique and rare taxa. 

Wetlands (with or without standing water)—Collect 10 

(more for very large sites) samples distributed evenly among 

habitats (or geomorphic settings) across the site. If there is 

standing water, then do jabs into the water with a net (see net 

types above) to collect the suspended macroinvertebrates. If 

minimal or no standing water exists, then use a net (see net 

types above) to do sweeps through the herbaceous vegetation. 

Targeted Sampling

This approach uses a timed spot search to find aquatic macroinvertebrates. Individuals are detected by carefully searching 

habitats where macros would be expected, particularly in and 

around a spring source. If flowing water is present, collect 

“grab” samples of aquatic macroinvertebrates by roiling 

substrates and capturing material that washes downstream into 

a net (see net types above). All of the available aquatic habitat 

types (e.g., banks, mid-channel, gravel, sand, cobble, boulder, 

bedrock, submerged wood, and emergent and submerged 

aquatic vegetation) should be sampled for a set time (small sites 

will require less time to sample than large sites). 

If there are minimal or no aquatic habitats, then the net could be 

swept through the herbaceous vegetation, particularly in areas 

that seem to be the wettest (where there may be standing water, 

and hence aquatic macroinvertebrates, during some periods).

Note the time spent searching: a total of 20 minutes is recommended for small sites, 40 minutes for medium sites, and 60 

minutes for large sites.

Lab Identification

If samples will be sent to a lab for identification, then they need 

to be immediately preserved in 90 percent ethanol (EtOH) in 

plastic bottles; 250 ml widemouth bottles work well. Label each 

sample with internal tags written on write-in-the-rain paper with 

the following information: site ID, date, and collector. 

Identifying and enumerating aquatic macroinvertebrates 

requires training and diligent attention to standardized procedures that provide for quality assurance and quality control. A 

laboratory should be chosen that follows general processing and 

identification guidelines that have been developed for bioassessment studies (e.g., Barbour et al. 1999). A recommended 

laboratory used frequently by the Forest Service is the Bureau 

of Land Management/Utah State University BugLab at the 

following address:

National Aquatic Monitoring Center 

Department of Watershed Sciences (WATS) 

Utah State University 

5210 Old Main Hill 

Logan, UT 84322–5210 

Forms and procedures for submitting samples to the BugLab 

can be found at http://www.usu.edu/buglab/.
50 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Field Identification

If basic field identification will be done, then either transfer the 

invertebrates to a white-bottom pan or leave them on the net to 

identify and count them. A technician that is reasonably familiar with different groups of aquatic invertebrates will identify 

common taxa, such as springsnails, stoneflies, caddisflies, and 

mayflies, using the “Key for Identifying Aquatic Macroinvertebrates” in appendix 12. An aquatic ecologist or fisheries 

biological technician may be able to identify invertebrates 

to order and perhaps family, which is the lowest taxonomic 

level possible in the field. Data from field identification would 

provide a very general taxonomic list. 

For field identification, record the following for each taxon 

within a sample: 

 Method—The sampling method used to capture the invertebrate. The choices are kick net, D-frame net, or hand net. 

 Collection ID—This could be the distance (0–20) from the 

spring source (for springs) or a location descriptor for wetlands. 

 Scientific name—Record the invertebrate taxon (order or 

family). 

 Number of individuals—Count and record the total number 

of individuals of each taxon captured in the sample.

 Specimen collected—Indicate whether or not a specimen 

was collected for that taxon.

 Number of specimens collected—Record the number of 

specimens collected for each taxon. 

Richness count—This is a simpler, field-based, approach, 

which involves counting the types of macroinvertebrates are 

at the site without identifying them. This provides a rough 

estimate of richness (the number of taxa) and evenness (how 

equal the numbers of individuals in the different taxa). This is 

a field-based approach that relies on observers to distinguish 

taxa, without having to know what they are. Because of the 

difficulty of distinguishing some taxa, this would be a very 

general assessment. The count is done by separating different 

types of macroinvertebrates (an ice-cube tray works well), and 

comparing newly encountered macroinvertebrates with the existing ones (one per cube). New macroinvertebrates are put in 

new cubes, while already observed macroinvertebrates are put 

in with the same taxa. This provides a rough estimate of how 

many different types of macroinvertebrates exist (richness), and 

the numbers within each taxon (used to calculate evenness).

Natural and Anthropogenic 

Disturbance

Record any disturbances observed at the site. This can provide 

managers with information on activities or structures that may 

be detrimentally affecting the structure and function of the site. 

It can be helpful to make notes about disturbances observed.

Hydrologic Alteration

Description—This is a list of activities or structures that have 

altered the natural hydrologic function of the system. This can 

provide managers with information on activities or structures 

that may be having a detrimental effect on the hydrologic function of the feature. Multiple answers are allowed.

How to measure and record—

q Water diversion—Water permanently diverted away from 

spring habitat (ditch, pipeline, spring box, or other form 

of dewatering).

q Water diversion—Water eventually returns to spring habitat.

q Upgradient extraction of surface water or groundwater 

(prespring emergence).

q Downgradient capture of surface water or groundwater 

(post-spring emergence).

q Extraction of water within a wetland.

q Extraction of water at spring source.

q Regulated water flow by impoundment/dam.

q Pollution.

q Flooding.

q Wells.

q Other: ___________.

q None observed.

Volume and Percent Diverted

Record the volume and percentage (to nearest 10 percent) of 

water being diverted (noted previously) at the time of inspection. Indicate whether this was a visual estimate or a measurement (e.g., flow meter). Inspect flow upstream and downstream 

of diversion, as well as water in the conveyance, if possible, to 

determine percentage being diverted. 

Soil Alteration

Description—This is a list of the major types of soil alteration 

found at the site. Multiple answers are allowed.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 51

How to measure and record—

q Channel erosion.

q Compaction.

q Debris flow.

q Deposition.

q Displacement of soil.

q Erosion (general).

q Evaporate deposition.

q Excavation. 

q Ground disturbance (general).

q Gully erosion.

q Mass wasting.

q Mining.

q Pedestals or hummocks (created by people or animals).

q Pedestals (small-scale, rain-splash induced).

q Pipes.

q Rill erosion.

q Ruts (from vehicle tread).

q Sheet erosion.

q Slump.

q Splash erosion/ soil crust.

q Wind erosion.

q Soil mixing/churning.

q Soil removal (peat mining).

q Trails (by people or animals).

q None observed.

q Other: ___________.

Structures

Description—This is a list of the kinds of structures present at 

the site. Multiple answers are allowed.

How to measure and record—

q Buried utility corridors.

q Enclosure (such as spring house, spring box, or concrete 

enclosure).

q Erosion control structure.

q Exclosure fence.

q Oil and gas well.

q Pipeline.

q Point source pollution.

q Power lines.

q Road (includes construction and maintenance).

q None observed.

q Other: ___________.

Recreation Effects

Description—This is a list of recreational activities in evidence 

at the site. Multiple answers are allowed.

How to measure and record—

q Camp sites.

q Tracks or trails by vehicles (all-terrain vehicle [ATV], 

4-wheel drive, etc.).

q None observed.

q Other: ___________.

Animal Effects

Description—This is a list of animal-related impacts to the site. 

This includes impacts from both domestic and wild animals. 

Multiple answers are allowed.

How to measure and record—

q Beaver activity.

q Feral animals.

q Grazing or browsing (by ungulates).

§ Wild animals.

§ Livestock.

q Trails by animals and people.

q Trampling (by ungulates, native or nonnative).

q None observed.

q Other: ___________.

Miscellaneous

Description—These are potential disturbances that do not fit 

in the categories described previously. Multiple answers are 

allowed.

How to measure and record—

q Fire.

q Tree cutting (timber harvest or other).

q Refuse disposal.

q None observed. 

q Other: ___________.
52 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Archeological, Paleontological, Cultural, 

or Historic Sites or Use

Description—This is a list of any archeological, paleontological, cultural, or historic sites or other human use of the site. 

Many springs in arid regions have a long history of use by 

Native Americans and others. Some have spiritual values associated with them. Some fens have preserved remains of extinct 

animals. Knowledge of sensitive sites will limit inadvertent 

damage to these resources.

How to measure and record—Record evidence of archeological, paleontological, and cultural resources or historic use (e.g., 

archaeological, paleontological, historic sites).

Management Indicator Tool

Responses to the Management Indicator Tool statements are 

used to identify potential need for management action based 

upon observation and information collected during the field guide 

implementation. This information may be useful for prioritizing 

sites needing additional monitoring or other management 

actions. The tool should be completed at the site, using a 

field crew consensus approach, and conclusions validated or 

confirmed later in the office based on a review of the data collected and other records or information available at the office 

(e.g., land status records, land and resource management plans). 

Some of the statements, particularly “Administrative Context,” 

may require review of records before the field visit.

This tool uses “true” or “false” answers, which by definition 

require interpretation by the field team and have undefined cutoffs. 

Make the best judgment possible and include comments and 

explanations where uncertainty or mitigating factors entered 

into the assessment. In particular, provide comments for all 

responses of False (No), Does not apply, or Unable to assess.

False answers indicate issues of concern that might pose 

problems for the long-term functioning of the GDE or when 

observed at multiple sites indicate a need for management 

attention. There is no summary scoring system based on the 

results of this tool. It is up to the specialist involved in data 

collection and the decisionmaker responsible for management 

to interpret the inventory results.

The following other resources were used for assessing management needs and for developing portions of the Management 

Indicator Tool. 

Assessing proper functioning condition for fen areas in the 

Sierra Nevada and Southern Cascade ranges in California: 

a user guide (Weixelman and Cooper 2009). 

A user guide to assessing proper functioning condition and 

the supporting science for lentic areas (Prichard 2003). 

Springs ecosystem assessment protocol scoring criteria

(Stevens and Springer in development).

Following are the 25 management indicator statements to address.

Aquifer functionality: No evidence suggests that the 

aquifer supplying groundwater to the site is being affected by groundwater withdrawal or loss of recharge.

GDEs exist where groundwater reaches the earth’s surface, 

often through complex and lengthy geologic flow paths. The 

consistent supply of groundwater maintains flows in springs 

and high water tables in wetlands. This supply of groundwater 

is essential to maintain the GDE and, in many cases, unique 

plant and animal communities. This statement asks whether 

activities exist that interrupt or deplete this supply—reducing 

flows in springs or lowering water tables in wetlands.

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 No evidence suggests that groundwater extraction is 

adversely affecting the site. 

 Evidence of soil saturation exists, or standing water is 

apparent. 

 Plants that are obligate wetland and/or facultative wetland 

species are abundant at the site, taking into consideration the 

setting and site potential.

 None of the adverse effects in the following list are 

observed.

This indicator would be answered “No” in the following 

circumstances:

 Groundwater extraction, such as pumping wells or mining 

that intersects the water table, damages aquifer functionality.

 There is depletion of recharge to the aquifer through paving, 

soil compaction, vegetation manipulation, etc. 

 Soil saturation in a wetland, or flow of a spring, is less than 

in the past. One indicator of this could be where upland and 

facultative upland plant species are encroaching into areas 

formerly dominated by obligate wetland and facultative 

wetland species, suggesting a loss of groundwater. Another 

indicator could be if hydric soils are present beyond the 

current extent of the GDE, suggesting that the GDE has 

decreased in size.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 53

The only definitive way to detect aquifer functionality issues is 

through installation and monitoring of piezometers in wetlands 

and frequent monitoring of flow in springs.

Watershed functionality: Within the watershed, no 

evidence suggests upstream/upgradient hydrologic 

alteration that could adversely affect the GDE site.

The focus of this statement is on surface water, although 

groundwater and surface water are connected in most watersheds and activities affecting one of these resources can potentially affect the other. The watershed that is the focus of this 

statement would generally be a 6th-level (12-digit) watershed 

hydrologic unit code. The condition of the surrounding uplands 

can greatly affect the condition of a GDE. Changes in upland 

condition can influence the magnitude, timing, or duration of 

overland flow events, which could result in erosion or deposition of sediment in the GDE. The purpose of this indicator is 

to determine if activities within the watershed have adversely 

affected the feature. Although a correlation can exist, the focus 

here is on whether the uplands are contributing to degradation 

of the GDE, and not on the condition of the uplands.

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 The site is receiving a normal range of surface flows, even if 

disturbance exists within its watershed. 

 None of the adverse effects in the following list are observed.

This indicator would be answered “No” in the following 

circumstances:

 Upslope road ditches and cross drainage structures were 

installed in a manner that concentrates overland flows and 

shallow groundwater away from the site, causing desiccation of soils. 

 Flow has been added from a diversion, and excessive erosion 

or deposition is taking place as a result of this increased flow.

 Trail development has intercepted, diverted, or concentrated 

overland flows initiating a headcut that is draining the site.

 Upslope road ditches, culverts, etc., are failing or in need of 

repair.

Water quality: Changes in water quality (surface or 

subsurface) are not affecting the GDE site.

GDEs are complex biogeochemical systems where water, 

nutrients, sediments, microclimate, and biota interact as part 

of the natural processes. The ecology of a GDE is affected by 

the quality of the water supporting the site. Changes in water 

quality can have detrimental effects on the flora and fauna. 

GDEs are susceptible to pollution from a number of activities. 

Pollutants may be toxic, which may harm or eliminate aquatic 

life. Inputs of nutrients (e.g., nitrogen, phosphorus) can increase 

the growth of aquatic vegetation and bacterial abundance and 

lower dissolved oxygen concentrations. These effects may 

cause intolerant macroinvertebrate communities to be replaced 

by communities that associated with impaired aquatic systems.

The geology of some watersheds naturally yields constituents 

(salts, iron, nutrients, calcium carbonates, etc.) that can inhibit 

growth for certain plant species. Examples of GDEs that have 

naturally limiting water quality conditions that favor some 

flora and fauna over others are thermal springs, travertine/tufa 

depositing springs, low pH springs, iron fens, and calcareous 

fens. Understanding the geology, soils, and water source is 

important to be able to accurately assess the causes of the water 

quality data. In some cases, unusual water chemistry values 

could be natural and, in other cases, they could be because of 

management activities. 

Examples 

This indicator would be answered “Yes” in the following 

circumstances:

 Water quality is within the expected range of variability. 

 None of the adverse effects in the following list are observed.

This indicator would be answered “No” in the following 

circumstances:

 Data collected indicate poor water quality (requires knowledge of expected range of variability for the site). 

 Sources of pollution such as mining waste or tailings, landfills, herbicides, pesticides, or accidental spills of hazardous 

chemicals and waste along roads exist.

 There has been excessive use by nonnative ungulates (such as 

wild horses and burros, cattle, and sheep) or native ungulates 

that have (1) deposited fecal matter and increased nutrients 

in the water or (2) damaged vegetation, allowing increased 

amounts of sediment and nutrients to enter the aquatic system. 

 Sewage disposal on site, or sewage from off-site septic 

systems or lagoons has allowed pollutants to leach into the 

groundwater and move to springs along a hydraulic gradient. 

 In some cases, excessive algae may be an indicator of nutrient loading in the water. 

 Vegetation shows signs of stress from chemicals in the water.
54 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Foul smells or discolored water should be further investigated 

to determine whether a water quality problem exists, or whether 

the foul smell is from natural anaerobic conditions and the 

discoloration is from a natural accumulation of organic matter. 

If a problem is identified, water samples should be collected 

and analyzed, and the results compared against relevant water 

quality criteria.

Landform stability: No evidence indicates humancaused mass movement or other surface disturbance 

affecting the GDE site stability. 

In general, stable landforms are at a state of equilibrium with 

physical conditions and processes that affect a site such as 

climate, slope, soil, soil moisture, and geology. Anthropogenic 

disturbances in the watershed, including the GDE, can cause 

instability in landforms. The intent of this indicator is to identify activities or causes of landform instability at the GDE site. 

Natural mass wasting can occur where groundwater discharges 

on a slope because geologic materials become saturated with 

water, the angle of repose is reduced to a very small value, and 

the material tends to flow like a fluid. This is because groundwater reduces grain-to-grain frictional contact. As a result, 

some discharge wetlands are associated with slope failures 

that are natural, but they could also be partially the result of 

management activities.

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 Only natural mass movement, such as slumping, occurs.

 None of the adverse effects in the following list are observed.

This indicator would be answered “No” in the following 

circumstances: 

 Excessive sediment deposition has occurred.

 Stream channel alteration has occurred, beyond what is 

natural.

 Streambank erosion or a headcut is affecting site stability.

 Slope failure has occurred from unnatural causes.

 A road cut or failing infrastructure (such as retaining walls, 

log cribs) is causing slope instability.

Runout channel: The channel, if present, is functioning 

naturally and is not entrenched, eroded, or otherwise 

substantially altered. 

Runout channels from springs or wetlands support flora and 

fauna that are an important and often unique part of the biodiversity of a site, therefore the condition of the runout channel 

is important to assess. Changes in channel and bank morphology 

or substrate composition can alter habitat.

Runout channels are groundwater-fed streams that emerge from 

spring orifices (referred to as spring brooks or spring runs) or 

within groundwater-fed wetlands. Surface drainage areas to 

these springs can be very small, often much smaller than the recharge area of the springs. The major differences in controls on 

the channel morphology found between the spring-dominated 

and runoff-dominated channels are the discharge regime and 

the sediment input (Griffiths et al. 2008). The hydrology unique 

to spring-dominated channels and the lack of fine-grained sediment input combine to create the observed differences. Channels downstream of springs are typically straight, or, if sinuous, 

they are without regularity to the pattern. Bars are absent or 

poorly defined, but islands or downed timber is common in the 

channel. Springflow-dominated channels are a special habitat 

of running waters because of the relatively uniform temperature 

and the deoxygenated groundwater contribution to the stream 

(Springer and Stevens 2009). Springflow-dominated systems 

may be sufficiently stable habitats to allow for evolutionary 

microadaptation and, ultimately, speciation (McCabe 1998). 

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 The runout channel is functioning naturally.

 None of the adverse effects in the following list are observed.

This indicator would be answered “No” in the following 

circumstances:

 Bank morphology has been changed by ungulate trampling, 

vehicles, or other activities.

 Channel morphology has been changed by excavation, ditching, or redirection.

 The channel is entrenched.

 Erosion of streambanks is beyond the natural range that 

would be expected at the site.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 55

Soil integrity: Soils are intact and functional. For 

example, saturation is sufficient to maintain hydric 

soils, if present; there is not excessive erosion or 

deposition.

The purpose of this indicator is to evaluate the condition of the 

soil and to determine if the soil has been affected by excessive 

disturbance. Management activities can alter the soil and 

the hydrologic conditions that affect the soil. In the case of 

wetlands, intact hydric soils are a useful indicator that the duration and frequency of saturation has been sufficient to maintain 

wetland soil characteristics. Soil saturation creates anaerobic 

conditions, which leads to the reduction, translocation, and accumulation of iron, manganese, sulfur, and carbon compounds 

(redoximorphic features). Saturation also slows decomposition 

of plant material, which can lead to the accumulation of peat 

(over long-term periods). This soil integrity indicator is intended 

to assess whether such hydric soils are being maintained in 

those areas where hydric soils would be expected. In the case 

of springs without hydric soils, the intent is to determine if soil 

disturbance (erosion, deposition, compaction, etc.) has occurred. 

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 Hydric soils are present and soil saturation is close to the 

ground surface.

 None of the adverse effects in the following list are observed.

This indicator would be answered “No” in the following 

circumstances:

 Soil compaction or erosion because of livestock, vehicles, 

or other sources.

 Desiccated peat or oxidized organic matter is observed at 

the site.

 Peat soils are churned because of livestock hoof action. 

(This refers to the stirring of the peat layer that causes organic matter to be mixed into the underlying mineral layer. 

The soil structure is altered and is massive or platy.)

 Pedestals created by hoof shear, hoof compaction, and 

disruption of root systems.

 Post holes/puddling that result from logging equipment, 

recreational vehicles, livestock, and wildlife.

Vegetation composition: The site includes anticipated 

cover of plant species associated with the site 

environment, and no evidence suggests that upland 

species are replacing hydric species.

Vegetation composition is an expression of environmental 

conditions and management activities. The abundance of plant 

species will respond to changes in hydrologic conditions at a 

GDE. In some cases, certain species disappear altogether from 

a site because of changes in water table or spring flow. Vegetation composition can also change because of disturbances and 

management activities. The relatively consistent availability of 

water at GDEs supports hydric plants, which are generally more 

abundant at GDEs than in the surrounding uplands.

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 Expected vegetation for the setting and environment is present, which would generally include OBL or FACW species 

of the Wetland Indicator Status (USFWS 1988). 

 Primarily native species.

This indicator would be answered “No” in the following 

circumstances:

 Wetland vegetation seems to have been greatly reduced or 

eliminated. 

 Overstory of wetland woody species but a lack of wetland 

understory species, suggesting recent hydrologic changes 

(because herbaceous vegetation is generally more responsive 

to changes in hydrology than woody species). 

 Evidence suggesting that upland species have increased. 

 Dominance by nonnative or invasive plants.

Vegetation condition: Vegetation exhibits seasonally 

appropriate health and vigor.

This statement is intended to evaluate the health or vigor of 

the vegetation, based on a visual assessment. The condition of 

vegetation can be adversely affected by management activities.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 Sites that have dense, robust vegetation growth that is 

healthy-looking in terms of leaf color, size, and shape. 
56 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

This indicator would be answered “No” in the following 

circumstances:

 Sites that have discolored, decadent, weakened, or unusually 

sparse vegetation.

 Evidence of severe grazing or browsing by livestock and/or 

native ungulates, such as hedged plants.

Threatened, endangered, or sensitive species; SOI/

SOC; or focal floral species: Anticipated floral species 

are present (will vary by ecological region and will 

require some baseline information).

Some GDEs support threatened, endangered, or sensitive species; SOI/SOC; or focal floral species. The intent of this indicator is to identify sites that support these important plant species. 

GDEs can be floristically diverse, supporting a large number 

of rare and uncommon vascular plant species and bryophytes. 

GDEs can be unique habitats that support a higher level of 

biodiversity than the surrounding landscape. An array of plant 

species is known to be endemic to, or inhabit, these locations.

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 Threatened, endangered, or sensitive species; SOI/SOC; or 

focal floral species were observed at a site whether or not 

they had been identified at the site before. 

 No threatened, endangered, or sensitive species; SOI/

SOC; or focal floral species were observed and none were 

anticipated.

This indicator would be answered “No” in the following 

circumstances:

 Threatened, endangered, or sensitive species; SOI/SOC; or 

focal floral species were not observed at a site but had been 

documented at the site previously.

 Threatened, endangered, or sensitive species; SOI/SOC; or 

focal floral species were expected to be at the site but were 

not observed.

Faunal species: Anticipated aquatic and terrestrial 

faunal species associated with the site environment 

are present.

Some GDEs have habitats that support aquatic and terrestrial 

faunal species. The intent of this indicator is to identify sites 

that support important animal species. 

Wetlands support many different types of animals, including 

invertebrates, fish, amphibians, reptiles, birds, and mammals. 

Because of the transitional nature of wetlands, both aquatic 

and terrestrial animals live in wetlands. Wetlands provide food 

sources, protection from weather and predators, resting sites, 

reproductive sites, and molting grounds for wildlife (Cooper 

1989). Wetlands provide this habitat function for many species 

of fish and wildlife, including some that are threatened or 

endangered. Many species of animals that are not typically 

considered to be wetland species also use wetlands.

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 Anticipated faunal species were observed at a site, whether 

or not they had been identified at the site before. 

 No faunal species were anticipated, and none were observed. 

This indicator would be answered “No” in the following 

circumstances:

 Anticipated faunal species were not observed at a site but 

they had been documented at the site previously. 

 Faunal species were expected to be at the site but they were 

not observed.

Threatened, endangered, or sensitive species; SOI/

SOC; or focal faunal species: Anticipated faunal 

species are present (will vary by ecological region 

and will require some baseline information).

GDEs can be unique habitats that support a higher level of 

biodiversity than the surrounding landscape. An array of 

threatened, endangered, or sensitive species; SOI/SOC; or focal 

faunal species is known to be endemic to, or use, GDEs. The 

intent of this indicator is to identify sites that support important 

animal species. 

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 Threatened, endangered, or sensitive species; SOI/SOC; or 

focal faunal species were observed, whether or not they had 

been identified at the site before. 

 No threatened, endangered, or sensitive species; SOI/SOC; 

or focal faunal species were anticipated, and none were 

observed.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 57

This indicator would be answered “No” in the following 

circumstances:

 Threatened, endangered, or sensitive species; SOI/SOC; 

or focal faunal species were not observed but had been 

documented at the site previously.

 Threatened, endangered, or sensitive species; SOI/SOC; or 

focal faunal species were expected to be at the site but were 

not observed.

Invasive species: Invasive floral and faunal species 

are not established at the site.

Invasive plant and animal species have a detrimental effect 

on the ecological functioning of GDEs. This statement asks if 

invasive animal or plant species have become established at 

the site. It is useful to know where invasive species have been 

established, so that controls can be implemented. Identifying 

the occurrence of invasive species before they infest a site is 

useful information.

Various characteristics of invasive species allow them to displace 

native vegetation at sites that have been disturbed by water 

impoundments, excessive grazing, recreation, and other activities. By displacing native vegetation, they reduce habitat that 

formerly provided critical nesting, feeding, and spawning habitat 

for wildlife species. A number of nonnative vertebrates and invertebrates have been introduced into springs in Western North 

America, and in some cases, populations of native aquatic 

species have either been reduced or extirpated as a result. 

Some plant species that are considered to be invasive in springs 

or wetlands, at least in some States, include purple loosestrife, 

tamarisk, common reed, reed canarygrass, and many others. 

Invasive animals could include the zebra mussel and many others.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 No invasive species (or very few individuals) were observed 

at the site.

This indicator would be answered “No” in the following 

circumstance:

 Invasive animal or plant species are established at the site.

Lists of invasive plants can be obtained for States and many 

counties or on line at http://plants.usda.gov/java/noxiousDriver.

Flow regulation: Flow regulation is not adversely 

affecting the site.

Alteration of surface or subsurface flow patterns may affect the 

functionality of a site. This statement is intended to determine 

if flow regulation has occurred at the site, which can have 

significant effects on the biota. For areas where wetland vegetation is important, a change in flow patterns may mean a change 

in vegetation type (wetland species to upland species), creating 

a site unable to function properly. For others, it may mean a 

decrease in extent of wetland or complete wetland loss.

Effects of diversion are similar to the consequences of a drought 

that causes springs and wetlands to become drier. In general, 

species richness declines as diversion increases, and functional 

shifts in the structure of aquatic and wetland communities occur. 

As diversion increases, intolerant aquatic taxa (e.g., mayflies, 

caddisflies, crenobiontics) are replaced by tolerant taxa (e.g., 

midges, beetles, corixids), and nonnative and upland vegetation 

becomes more abundant. 

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 No flow regulation exists at the site.

 Flow regulation structures are stable, accommodate flows, 

and do not adversely affect the ecology of the site.

 Diversions remove very small amounts of water and have 

minimal effects on ecology.

This indicator would be answered “No” in the following 

circumstances:

 There exists channelization or redirection of flow, delivery 

of water through pipes and concrete channels to tanks and 

reservoirs, excavation and installation of spring boxes, ditching wetlands to drain them, or impounding spring sources. 

(These structures are designed to capture and divert water for 

uses such as livestock watering, domestic use, or irrigation.)

 Flow diversion is causing the area of wetland vegetation and 

soils to contract.

Construction and road effects: Construction, reconstruction, or maintenance of physical improvements, 

including roads, are not adversely affecting the site. 

Roads can cause negative ecological effects to ecosystems, 

plants, and wildlife. The effects of road construction and 

operation on wetlands and springs include negative effects 
58 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

from changes to the chemistry and biology of the local area to 

changes in hydrology that go beyond the immediate area of the 

road. Loss of wildlife habitat, loss of species, and biodiversity 

are other consequences of such changes. In addition, roads are 

barriers that can cause habitat fragmentation and edge effects, 

which may affect some plant and animal species. Roads are 

also corridors that can facilitate the spread of invasive species.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 No evidence suggests that construction or roads are affecting 

the GDE.

This indicator would be answered “No” in the following 

circumstances: 

 Within the site, roads have caused trampling, soil compaction, 

erosion, disturbance (because of noise or motion), pollution, 

nutrient loading, or introduction of invasive plant species.

 Road is channelizing runoff and delivering sediment to the 

site. 

 Physical improvements, such as buildings, latrines, water 

development structures, piping, and parking lots, are affecting the site.

 Stormwater runoff from a road or parking lot is entering a 

wetland. 

Fencing effects: Protection fencing and exclosures 

are appropriate and functional.

Fences are sometimes used to exclude animals or people from 

spring or wetland sites to prevent damage to vegetation, alteration 

of sediment flux, or adverse affects on water quality. Proper 

placement and maintenance of fences is required to meet conservation objectives. This indicator assesses if the fences are 

appropriately designed, located, and maintained, and if they are 

working as intended.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 Fencing was properly designed and is functioning to exclude 

whatever it was intended to exclude, such as livestock, wild 

animals, vehicles, and recreation use.

This indicator would be answered “No” in the following 

circumstances:

 Fence is down, damaged, or broken.

 Fence was not designed or constructed in a manner that effectively protects the ecologically valuable portions of the site.

Herbivore effects: Herbivory is not adversely 

affecting the site.

This indicator documents whether grazing or browsing by 

native or nonnative animals is adversely affecting the site. This 

refers to effects from animals such as cattle, sheep, horses, 

burros, elk, deer, or moose. 

Many springs and wetlands have been altered by grazing and 

trampling of livestock, as well as other nonnative and native 

ungulates. Excessive grazing in GDEs can damage or alter vegetation, lead to increased water temperature, cause soil erosion 

(including streambank erosion), and add sediment and nutrients 

to aquatic systems. Those changes can damage habitat for wildlife, fish, and other aquatic fauna, such as macroinvertebrates.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 No evidence indicates adverse effects from grazing or 

browsing by native or nonnative ungulates.

This indicator would be answered “No” in the following 

circumstances:

 Native or nonnative ungulates have caused excessive 

removal of vegetation, abnormally low height (including 

hedging of shrubs) or cover of vegetation, or major changes 

in species composition. 

 Native or nonnative ungulates’ hoof action has caused 

trampling of vegetation, soil erosion, or other ground 

disturbance.

Recreational effects: Recreational uses, including 

trails, are not adversely affecting the site. 

Recreational activities can negatively affect GDEs. Off-road 

vehicle use is increasing on NFS lands and has damaged 

many wetland and spring habitats. Sada (2001) documented 

how trampling by recreationists affected the abundance and 

distribution of spring-dwelling mollusks. The effects on 

springs is similar to those caused by excessive livestock and 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 59

wildlife activity in riparian and aquatic systems, where it has 

degraded riparian vegetation and increased water temperature, 

the amount of fine substrates, and nutrient loading (Fleischner 

1994; Kauffman and Krueger 1984). 

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 None of the adverse effects in the following list are 

observed.

This indicator would be answered “No” in the following 

circumstances:

 Camping, hiking, and associated refuse have adversely 

affected the site.

 Recreation use along a spring brook has caused decreased 

vegetation height or cover (through trampling or other damage).

 Vehicles have caused erosion, soil compaction, damage to 

vegetation, or other adverse effects.

 Other recreational activities (trails, horseback riding, etc.) 

have adversely affected the site.

Other disturbance effects: Wildland fire, insect, disease, wind throw, avalanches, or other disturbances 

are not adversely affecting the site.

This indicator documents adverse effects from disturbances 

not captured in other statements, such as fire, blow down, pest 

infestation, disease, and avalanche. 

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 None of the adverse effects in the following list have had a 

significant adverse affect on the site.

This indicator would be answered “No” in the following 

circumstances:

 Significant amounts of dead or dying vegetation (particularly trees and shrubs) from insect infestation, disease, or 

wildfire are found in the site.

 Evidence suggests that blow down, pest infestation, disease, 

avalanches, debris flow, or other natural disturbances have 

had a significant adverse affect on the site.

Cultural values: Archaeological, historical, or tribal 

values will not affect inventory, restoration, use, or 

management of this site. 

Many springs, particularly in the Southwestern United States, 

have cultural and or historical significance that could require 

consultation with tribes or State historic preservation offices.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 No evidence indicating archaeological, historical, or tribal 

resources at the site.

This indicator would be answered “No” in the following 

circumstances:

 Archaeological, historical, or tribal resources could be affected by inventory, restoration, use, or management of the 

site.

 Site sacredness is recognized by tribes or nontribal agencies.

 Site has potential for National Register of Historic Places

status.

 Artifacts, petroglyphs, ruins, water works, or dwelling sites 

are present.

Land ownership: The entire site and immediate area 

are under the jurisdiction and management of the 

Forest Service.

This indicator simply documents that the site is managed by the 

Forest Service and, thus, the land manager has the authority to 

control undesirable or unauthorized activities at the site.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 Entire site is within Forest Service jurisdiction.

This indicator would be answered “No” in the following 

circumstance:

 Part, or all, of the site is not within Forest Service 

jurisdiction.
60 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Other landowner actions: Activities or management 

on lands outside Forest Service jurisdiction are not 

adversely affecting the site.

This indicator documents whether the site is under threat from 

actions by adjacent landowners.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 None of the adverse effects in the following list are observed.

This indicator would be answered “No” in the following 

circumstances:

 A large pumping well is located adjacent to the site, off of 

NFS lands, and is dewatering the site.

 Other activities off of NFS lands are adversely affecting the 

site.

Land management plan: The land and resource management plan provides for effective site protection.

Forest or grassland plans define desired conditions or standards 

and guidelines for management of forest resources. 

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 The forest or grassland plan states that springs and wetlands 

are managed to promote long-term viability of ecological 

function.

This indicator would be answered “No” in the following 

circumstance:

 The forest plan does not recognize that springs and wetlands 

are managed to promote long-term viability of ecological 

function.

Environmental compliance: Authorized and administrative uses are in compliance and are not adversely 

affecting the site.

Water developments are authorized under special-use authorization regulations. This indicator is used to alert the land 

manager of unauthorized activities that need to be addressed.

Examples

This indicator would be answered “Yes” in the following 

circumstance:

 None of the adverse effects in the following list are observed.

This indicator would be answered “No” in the following 

circumstances:

 A water development was not constructed as specified in the 

permit.

 Grazing within the site is not in compliance with allotment 

management plan requirements.

Water uses: There are no substantial water uses in 

the watershed or in the aquifer supplying groundwater to the site that could directly or cumulatively 

adversely affect the GDE.

The purpose of this indicator is to assess the scope and extent 

of water use (including that from water rights) within the 

watershed and/or aquifer to assess the potential for direct or 

cumulative adverse affects to the GDE. 

Water use from surface or groundwater sources should be 

accounted for under either State or Federal authority. All water 

use, whether exempt from State application procedures or 

not, needs to be properly documented and tracked relative to 

the amount of water used and location of withdrawal and use. 

Information from the Water Rights and Uses (WRU) database/

site visit field form, which can be included in the GDE inventory process, is used to assess if there is substantial water use, 

individually or cumulatively, from water uses. 

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 The density of water uses and water rights is small relative 

to streamflow availability or aquifer capacity.

 Water uses and water rights that affect the site have been 

inventoried or accounted for and are being used as intended 

or within the limits of the right or exemption.

 Infrastructure adjacent to the site or within the watershed has 

evidence of maintenance and is functioning well.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 61

This indicator would be answered “No” in the following 

circumstances:

 The density of water uses and water rights is moderate to 

high relative to streamflow availability or aquifer capacity.

 Water uses and water rights have not been inventoried; 

many uses are unidentified or unknown, with little to no 

information on amount or frequency of use. 

 Infrastructure adjacent to the site or within the watershed is 

extensive, with no inventory information to assess the extent 

of infrastructure and water use.

Water rights: Water rights have been filed for the site 

under State law or water uses exempted under State 

law are documented. Forest Service Federal reserved 

rights are documented as appropriate. Third-party 

water use is in accordance with all elements of the 

water right or conditions of the exemption and with 

the Forest Service authorization that allows the use.

The purpose of this indicator is to assess the water rights and 

water uses disposition of the site (see description under previous 

“water uses” section). Information from the WRU database and 

site visit field form, which can be included in the GDE inventory process, is used to assess if there is substantial water use, 

individually or cumulatively, from water uses.

Examples

This indicator would be answered “Yes” in the following 

circumstances:

 A reasonable amount of water is being consumed for the 

specific purpose. Amount and timing of water withdrawal is 

comparable to similar uses at sites or watersheds with similar 

conditions. 

 If metered, metering is accurate and measurements are used 

in assessments.

 The water right or use is valid and used in accordance with 

specifications of the right or use.

 Infrastructure and diversions are in good working condition.

This indicator would be answered “No” in the following 

circumstances:

 Water right or use is in violation of exemptions and is not 

authorized under State law or subject to forfeiture.

 Water is not metered and is required to be metered under 

State law or special-use permit.

 Infrastructure is not maintained and water use is not controlled.
62 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 63

Post-Field Survey Activities (in office)

After the field survey, additional activities need to be completed in the office or laboratory to supplement or enhance the 

field data. These activities are described in the following list 

(in the same manner they are listed in the “Using the Level II 

Field Guide” section in the beginning of this field guide).

Obtain or Verify Data 

Based on the location data (UTM or latitude/longitude) acquired 

at the site, the following are examples of attributes that can be 

determined, verified, or updated in the office, primarily with 

GIS tools:

 Watershed(s) hydrologic unit codes.

 Ecological system. 

 Local feature-type name.

 Site name (an existing site name that was not known at the 

field visit may exist).

 Primary lithology (groundwater source aquifer).

 Secondary lithology.

Laboratory Analyses

If samples or specimens were collected in the field, then they 

need to be transferred to a location where they can be analyzed. 

Plant specimens should be taken to a botanist or herbarium for 

identification. Macroinvertebrate specimens should be sent to 

a laboratory that follows general processing and identification 

guidelines for identification (described in the Lab Identification 

part of the Aquatic Macroinvertebrates section). Water samples 

and soil samples should be sent to a laboratory that follows 

standardized guidelines of quality assurance.

Implement Data Management and 

Interpretation Procedures

Field data recorded either on paper forms or field data recorders 

will need to be entered into the corporate database. A significant 

amount of time needs to be allotted for data entry from paper 

forms. The database can generate summaries for each attribute 

and those should be reviewed for obvious errors that might have 

been made in recording or entering the data. A site summary 

can be generated in the database as well, which includes all of 

the attributes and the basic site information.

Photos taken with a digital camera need to be downloaded, 

labeled, and stored in a location that is associated with the other 

site information. Handwritten materials such as drawings and 

notes should be scanned into electronic format and stored in a 

location that is associated with the other site information.

Validate and Confirm Management 

Indicator Tool Entries

The responses to the Management Indicator Tool should be 

compared to the summarized field data in the office. This will 

either confirm the field responses or provide information that 

can be used to edit the field responses. For example, it may 

have been noted that there were no invasive species at the site, 

but the summarized data in the office may indicate that there 

were indeed significant amounts of invasive plants or animals. 

The response to the statement on invasive species would then 

be updated based on the summarized field data.

Analyze and Evaluate Collected 

Information

Detailed techniques for analyzing and evaluating the data collected with this field guide are not described in this field guide.
64 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 65

Glossary

Some definitions are taken from Mitsch and Gosselink (2007). 

anoxia—Waters or soils with no dissolved oxygen.

aquifer—A saturated underground layer of water-bearing 

permeable rock or unconsolidated materials (gravel, sand, silt, 

or clay) from which groundwater can be extracted using a well. 

An aquifer can be confined, unconfined, or partially confined. 

The aquifer can be perched, local, or regional. Aquifers are 

connected to the hydrologic cycle through recharge, within and 

between unit flow, and through discharge.

artesian—Condition in which a confined aquifer is under 

pressure such that the static level within a cased borehole 

rises above an impermeable (confining) layer (e.g., peat layer) 

or in which water discharges to the surface from an unlined 

borehole.

base-flow stream—A perennial stream supported by groundwater discharge during periods of low or no precipitation or 

snowmelt.

bog—A peat-accumulating wetland that has no significant inflows or outflows and supports acidophilic mosses, particularly 

Sphagnum. In general, bogs are supported by precipitation.

bryophytes—Nonvascular land plants (mosses, liverworts, and 

hornworts) that have tissues and enclosed reproductive systems 

but lack vascular tissue that circulates liquids. They neither 

have flowers nor produce seeds because they reproduce via 

spores.

Carolina Bay—Elliptical depressions or shallow basins that 

occur throughout the Southeastern United States Coastal 

Plain. Their hydrology is dominated by precipitation inputs 

and evapotranspiration losses, and they range from nearly 

permanently inundated to frequently dry.

cave—A natural underground space formed by various geologic processes. Caves are common in karst terrain and areas 

of psuedokarst.

cienega—Usually a wet, marshy area at the foot of a mountain, 

in a canyon, or on the edge of a grassland where groundwater 

reaches the surface. Often, a cienega does not drain into a 

stream but instead evaporates. Also called helocrene.

crenobiontic—Organisms that live only in springs.

exposure spring (one of the spheres of discharge, as described 

by Springer and Stevens 2009)—Groundwater is exposed at 

the land surface but does not have surface inflow or outflow. 

Exposure springs occur in karst (sinkholes) and psuedokarst 

(lava flows) but could form in other types of vertical conduits 

into an aquifer.

fen—In general, wetlands that develop where a relatively constant supply of groundwater to the plant rooting zone maintains 

saturated conditions most of the time and the water chemistry 

reflects the mineralogy of the surrounding and underlying soils 

and geological materials. The U.S. Fish and Wildlife Service 

(1999) uses two criteria to classify a wetland as a fen: (1) the 

wetland is primarily supported by groundwater, and (2) the 

wetland has organic soils meeting the U.S. Department of Agriculture, Natural Resources and Conservation Service (2010) 

definition of a histosol or a histic epipedon in at least some 

part of the contiguous wetland.

fibric—Organic soil material that contains 3/4 or more recognizable fibers (after rubbing between fingers) of undecomposed 

plant remains. Bulk density is usually very low and waterholding capacity very high. Also referred to as peat.

flark—See string and flark microtopography. 

forb—Herbaceous flowering plant that is not a graminoid.

fountain spring (one of the spheres of discharge, as described 

by Springer and Stevens 2009)—Cool, artesian springs that are 

forced above the land surface by artesian or gas pressure.

geyser (one of the spheres of discharge, as described by 

Springer and Stevens 2009)—Geothermal springs that emerge 

explosively and usually erratically. A geyser is a hot spring 

characterized by intermittent discharges of water that are 

ejected turbulently by a vapor phase.

graminoid—True grasses (Poaceae) or grass-like plants, such 

as sedges (Cyperaceae) or rushes (Juncaceae).

groundwater—All water below the ground surface, including 

water in the saturated and unsaturated zones.

groundwater-dependent ecosystems (GDEs)—Communities 

of plants, animals, and other organisms whose extent and life 

processes are dependent on access to or discharge of groundwater.
66 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

gushet (one of the spheres of discharge, as described by 

Springer and Stevens 2009)—Discrete sources of flow pouring 

from cliff faces. Gushets typically emerge from perched, 

unconfined aquifers, often with dissolution enhancement along 

fractures, exhibit thin sheets of water flowing over rock faces.

hanging garden or wet wall (one of the spheres of discharge, 

as described by Springer and Stevens 2009)—Springs that emerge 

along geologic contacts or fractures and seep, drip, or pour onto 

underlying walls. Hanging gardens in the Southwestern United 

States typically emerge from perched, unconfined aquifers in 

Aeolian sandstone units. 

helocrene (one of the spheres of discharge, as described by 

Springer and Stevens 2009)—Low-gradient springs and/or 

wetlands; often indistinct or multiple sources of groundwater. 

Also called wet meadows or cienegas.

hemic—Organic soil material at an intermediate degree of 

decomposition that contains 1/6 to 3/4 recognizable fibers (after 

rubbing between fingers) of undecomposed plant remains. Bulk 

density is usually very low and water-holding capacity very 

high. Also referred to as mucky peat.

herbaceous—A plant that has leaves and stems that die down 

to the ground at the end of the growing season. They have no 

persistent woody stems.

hillslope (one of the spheres of discharge, as described by 

Springer and Stevens 2009)—Springs and/or wetlands on a 

hillslope (generally 20- to 60-degree slope), often with indistinct or multiple sources of groundwater.

histic epipedon—An 8- to 16-inch layer at or near the surface 

of a mineral hydric soil that is saturated with water for 30 

consecutive days or more in most years and contains a minimum of 20 percent organic matter when no clay is present or 

a minimum of 30 percent organic matter when clay content is 

60 percent or greater. Soils with histic epipedons are inundated 

or saturated for sufficient periods to greatly retard aerobic 

decomposition of the organic surface and are considered to be 

hydric soils.

histosol—Histosols (organic soils) develop under conditions 

of nearly continuous saturation and/or inundation. All histosols 

are hydric soils except folists, which are freely drained soils 

occurring on dry slopes where excess litter accumulates over 

bedrock. Organic hydric soils are commonly known as peats

and mucks.

hypocrene (one of the spheres of discharge, as described by 

Springer and Stevens 2009)—A buried spring where flow does 

not reach the surface. This term is common to the Southwestern 

United States. Elsewhere, these features may be equivalent to 

shallow groundwater areas, including fens.

hyporheic zone—Area of a stream bed and bank where surface 

and ground waters mix. A similar area, the hypolentic zone, 

exists in lakes and ponds.

insurgence—The point of inflow for surface water into subsurface conduits in karst areas.

jurisdictional wetlands—Those areas that are inundated or 

saturated by surface or ground water (hydrology) at a frequency 

and duration sufficient to support and that, under normal circumstances, do support a prevalence of vegetation (hydrophytes) 

typically adapted for life in saturated soil conditions (hydric 

soils). Wetlands generally include swamps, marshes, bogs, and 

similar areas (40 Code of Federal Regulations 232.2(r)). 

karst—A terrain or type of topography generally underlain 

by soluble rocks, such as limestone, gypsum, and dolomite, in 

which the topography is chiefly formed by dissolving the rock; 

karst is characterized by sinkholes, depressions, caves, and 

underground drainage. Psuedokarst is an area of depressions, 

caves, and internal drainage that result from volcanic activity. 

limnocrene (one of the spheres of discharge, as described by 

Springer and Stevens 2009)—Groundwater emerges in one or 

more pools.

marsh—A frequently or continually inundated wetland

characterized by emergent herbaceous vegetation adapted to 

saturated soil conditions. 

mineralized mounds (one of the spheres of discharge, as 

described by Springer and Stevens 2009)—Springs that 

emerge from (usually carbonate) precipitate mounds. 

minerogenous—See minerotrophic peatlands.

minerotrophic peatlands—Peatlands that receive water that 

has passed through mineral soil. Also called minerogenous 

hydrological systems.

muck—Organic soil material in which the original plant parts 

are not recognizable. Contains more mineral matter and is 

usually darker in color than peat. Also referred to as sapric

material.

mucky peat—Organic soil material in which a significant part 

of the original plant parts are recognizable and a significant part 

is not. Also referred to as hemic material.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 67

Natural Resource Manager (NRM) Automated Lands

Program (ALP) database—The Forest Service national ALP 

is an information management system that contains all land 

status data for Forest Service managed land, including land 

survey, ownership, use restrictions, and boundaries.

NRM-Infrastructure (INFRA) database—NRM-INFRA 

is a Forest Service data management system that includes a 

collection of Web-based data entry forms, reporting tools, and 

Geographic Information System tools that enable forests to 

manage and report accurate information about their inventory 

of constructed features and land units as well as permits sold to 

the general public and to partners.

NRM-Natural Resource Information System (NRIS) Water

Rights and Uses database—The NRIS is a set of Forest Service 

corporate databases and computer applications that contain basic natural resource data. The Water Rights and Uses database 

tracks core information about State and federally recognized 

water rights and uses. It also tracks related information about 

beneficiaries, purpose, quantity, and periods of water use. 

ombrogenous—Peatland with inflow from precipitation only. 

Also called ombrotrophic.

organic soil—Organic soils (histosols) develop under conditions of nearly continuous saturation and/or inundation. All 

organic soils are hydric soils except folists, which are freely 

drained soils occurring on dry slopes where excess litter accumulates over bedrock. Organic hydric soils are commonly 

known as peats and mucks.

peat—Organic soil material that is undecomposed or weakly 

decomposed. The plant remains are distinct and identifiable. 

peatland—A generic term for any wetland that accumulates 

partially decayed plant matter (peat).

phreatophyte—Plant whose roots generally extend downward 

to the water table and customarily feed on the capillary fringe. 

Phreatophytes are common in riparian habitats. Term literally 

means “well” plant or water-loving plant. 

piezometer—Small-diameter well open at a point or over a 

short length in the aquifer to allow measurement of hydraulic 

head at that location. 

pocosin—Peat-accumulating, nonriparian freshwater wetland, 

generally dominated by evergreen shrubs and trees and found 

on the Southeastern Coastal Plain of the United States. The 

term comes from the Algonquin word for “swamp on a hill.”

redoximorphic features—Features formed by the reduction, 

translocation, and/or oxidation of iron and manganese oxides; 

used to identify hydric soils.

rheocrene (one of the spheres of discharge, as described by 

Springer and Stevens 2009)—Flowing springs that emerge 

directly into one or more stream channels.

riparian—Pertaining to the bank of a body of flowing water; 

the land adjacent to a river or stream that is, at least periodically, 

influenced by flooding. Riparian sometimes is used to indicate 

the banks of lakes and ponds subject to period inundation by 

wave action or flooding.

sapric—Organic soil material that contains less than one out of 

six recognizable fibers (after rubbing between fingers) of undecomposed plant remains. Bulk density is usually very low, and 

water-holding capacity very high. Also referred to as muck. 

seep—A discharge of water that oozes out of the soil or rock 

over a certain area without distinct trickles or rivulets.

specific conductance—A measure of an aqueous solution’s 

ability to carry an electrical current (also called electrical 

conductance or conductivity).

spring—A place where groundwater flows naturally from the 

earth into a body of surface water or onto the land surface.

spring brook—Runout channel from a spring, which may 

become a stream at some distance from the spring source.

spring source—The location where the spring emerges from 

the ground onto the land surface. Also referred to as the spring 

orifice.

string and flark microtopography—Slow groundwater 

movement through broad, gently sloped peatlands forms a 

series of linear hummock ridges called strings, separated by 

parallel hollows known as flarks. Strings and flarks are arranged 

perpendicularly to the flow of water through the peatland and 

can form a regular pattern of parallel ridges and hollows or an 

intricate, braided or branching (anastomosing) pattern.

swamp—Wetland dominated by trees or shrubs.

Terrestrial Ecological Unit Inventory (TEUI)—The national 

program of ecological classification within the Forest Service 

that was developed to classify ecological types and map ecological units to a consistent standard across National Forest System 

lands. TEUI establishes terrestrial mapping units derived from 

a combination of core data sets, which uniquely characterize a 

spatial region, including climate, geology, geomorphology, soil 

regime, and vegetation.
68 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

upland—Land that is not influenced by a consistent source of 

surface water or groundwater and, therefore, does not support 

wetland vegetation or hydric soil development as would a 

wetland or riparian area.

wet meadow—Area that is saturated with water for much of 

the year but does not have standing water, except for brief 

periods, during the growing season.

wetland—In general, wetlands are lands on which water 

covers the soil or is present either at or near the surface of the 

soil or within the root zone, all year or for varying periods of 

time during the year, including during the growing season. 

The U.S. Fish and Wildlife Service defines wetlands as “lands 

that are transitional between terrestrial and aquatic systems 

where the water table is usually at or near the surface or the 

land is covered by shallow water...(and) have one or more of 

the following three attributes: (1) at least periodically, the land 

supports predominantly hydrophytes; (2) the substrate is predominantly undrained hydric soil; or (3) the substrate is nonsoil 

and is saturated with water or covered by shallow water at 

some time during the growing season of each year” (Cowardin 

et al. 1979). See also jurisdictional wetlands.

wetland indicator status—A system of categorizing plant species in terms of their probability of occurring in wetlands. The 

system was developed by the U.S. Fish and Wildlife Service 

(1988). It has five general categories: obligate, facultative 

wetland, facultative, facultative upland, and upland. Obligate 

species almost always occur in wetlands, whereas upland species almost never occur in wetlands, as described in table 9.

Wetland indicator status Code Estimated probability a species occurs in wetlands

Obligate OBL Almost always (99%)

Obligate – OBL –

Facultative wetland + FACW +

Facultative wetland FACW Usually (67–99%)

Facultative wetland – FACW –

Facultative + FAC +

Facultative FAC Equally likely to occur in wetlands or

nonwetlands (34–66%)

Facultative – FAC –

Facultative upland + FACU +

Facultative upland FACU Not usually (1–33%)

Facultative upland – FACU –

Upland + UPL +

Upland UPL Almost never (1%)

Table 9.—Wetland indicator status codes and descriptions (USWFS 1988).
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 69

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classification and mapping technical guide. Version 1.0. Washington, DC: U.S. Department of Agriculture, Forest Service, 

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geomorphic classification system. Washington, DC: U.S. 

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Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 71

Appendix 1. Order of Data Collection

The methods are generally presented in the recommended 

order that they should be conducted on the site. The order 

presented here is partially intended to minimize the amount of 

walking on the groundwater-dependent ecosystems (GDE) site 

and the number of trips into or across the site to avoid trampling the soil and vegetation. The number of passes (one way) 

along each transect should be kept to a minimum. 

Recommended Order of Collecting 

Field Data

1. Wildlife (mammals, birds, etc.) observations upon arrival 

at site.

2. Water quality—surface water (if done).

3. Aquatic macroinvertebrates.

4. Location and geologic information (Universal Transverse 

Mercators, elevation, etc.).

5. Determine extent (edge) of GDE, and determine the longest 

axis.

6. Establish transect locations (starting points)—walking just 

outside the GDE edge if possible. 

a. Vegetation.

i. For each transect—

(a) Quadrats for lower layer (primarily herbaceous).

(b) Line intercept for shrub and tree layer.

(c) Belt transects for tree count (not necessary if no 

trees).

b. Soils. 

i. Soil core and soil data collection.

c. Hydrology.

i. Water quality—subsurface water (use borehole from 

soil core or augered hole for water table).

ii. Water quantity.

(a) Water table depth.

(b) Flow. 

(c) Spring brook measures (if applicable).

7. Additional species (plant) search.

8. Aquatic and terrestrial fauna (macroinvertebrates are done 

earlier).

9. Photos.

10. Sketch map of site.

11. Natural and anthropogenic disturbances. 

12. Management indicator tool.
72 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 73

Appendix 2. Job Hazard Analysis

U.S. Dept. of Agriculture

Forest Service

JOB HAZARD ANALYSIS (JHA)

References-FSH 6709.11 and-12

(Instructions on reverse)

1.	WORK PROJECT/ACTIVITY

Field Data Collection

2.	LOCATION 3.	UNIT

4.	NAME OF ANALYST 5.	JOB TITLE 6.	DATE PREPARED

January 2010

7. TASK/PROCEDURES 8. HAZARDS 9. ABATEMENT ACTIONS

1. Driving from either official or

temporary duty station to field

location

a. Hazardous road conditions during

some portions of the year

 Drive with extreme caution.

 All field personnel attend defensive driving class renewed at least every three

portions of the year.

 See “Winter Travel” and “General Driving” JHA.

b. Driving in off-road situations with or

without four-wheel drive

 All new personnel receive training on the use and operation of four-wheel drive

vehicles.

 Drive with extreme caution.

c. Vehicle breakdown and unable to

get to shelter

 Ensure that each vehicle is equipped with a seasonal survival kit that has been

inspected and includes all items that are necessary.

d. Cell phones  Absolutely no using cell phones while driving a Government vehicle. This includes

texting and talking.

e. Female traveling alone  Avoid hotel rooms on the ground floor. Do not accept a room with adjoining door

entry. Keep cell phone handy and fully charged. Wear a wedding ring. Park in well

lit areas.

2. Foot travel a. Slips, trips, and falls  Wear nonskid boots that are appropriate for conditions.

 Watch where walking.

 Stay on trails when able.

 Use a walking stick when necessary.

b. Allergic reaction to insect bites

(e.g., bee stings)

 Ensure that all personnel with known allergic reactions to insect bites carry

appropriate medication. In addition, the allergic individuals should make sure

that their partner knows where the medication is kept and can administer it in an

emergency situation.

 In case of a bite or sting, watch subject closely for any allergic reaction. Call 911

or local emergency number and evacuate immediately if any reaction away from

injury site is observed.

c. Branches striking eyes  Keep a safe distance from partner.

 Wear protective eyewear.

d. Crossing shallow streams  Always work with a partner when planning stream or river crossings with water

depths over the knees. Choose crossing sites with shallow water, slow currents,

and gradual slopes. Avoid crossing sites with water over mid-thigh depths or

swift current.

 Use pole or walking stick to help maintain balance with three-point support. Move

one foot or pole at a time.

 Watch for and avoid large, wet, rounded rocks because they may be slippery.

 Be especially alert to the possibility of one foot becoming entrapped in rocks or

branches and current forcing individual off balance and under water.

 Carry a rope or throw rope long enough to reach across the entire width of the

crossing.

 Make the crossing one person at a time with one person on the bank at all times.

Stretch the safety rope between the person on the bank and the person crossing.

 Logs should be used as last alternative and should be of sufficient size, dry, and

algae free.

 Leave vest unbuttoned, remove workbelt from waist, disconnect waist and

sternum straps on pack, and be prepared to ditch any equipment if you are

unable to recover from a fall.

 Protect feet with proper footwear such as waders. Bring dry socks and footwear

to wear during field work and hiking.

 Do not cross streams during unfavorable weather.
74 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

3. Use of snowmobile to travel to the

field location

 See “Snowmobile Use” JHA.

4. Use of boat to travel to the field

location

 See “Boat Travel” JHA.

5. Use of all-terrain vehicle to travel to

the field location

 See “ATV Travel” JHA.

6. Driving FS/GSA vehicles  See “General Driving and 15 Passenger Vans” JHA.

7. Overnight travel  See “Overnight Travel” JHA.

8. Office work  See “Office Work” JHA.

9. Conducting field work a. Use of hand tools such as hand

axe, pruning saw, and shovel

 When traversing slopes, carry hand tools on the downhill side.

 Hand axes should always be carried sheathed with leather flap snapped shut.

 Do not carry long handled tools over shoulder, or hatchets unsheathed in

belt-loop.

b. Dehydration  Consume (in addition to regular meals) fruit and liquids that replace the loss

of carbohydrates and maintain blood sugar levels at normal limits. Drink water

regularly. Make sure you carry enough water. Take frequent breaks. Avoid open

sunny areas if weather is extreme. Seek shaded areas.

c. Hypothermia  Prevent hypothermia by planning ahead and using your gear to stay warm and

dry.

 On cool days be aware of overheating and then rapidly cooling down.

 Dress appropriately and in layers to account for temperature extremes.

 Stay hydrated and eat high-energy foods.

 See “Winter Travel” JHA for more detailed information.

d. Poisonous plants present

(e.g., poison ivy)

 Make sure that crew members can identify poisonous plants in their work area.

 Wear gloves and long-sleeve shirts.

 Wash affected area with soap and water as soon as possible or use ivy-off

products when water is not available.

 Wash potentially contaminated clothing as soon as possible after returning from

the field.

e. Falling branch or tree  Wear hardhat.

 Use extra caution during high-wind events.

f. Insect bites  Use appropriate insect repellent.

 Secure bottom of pant legs to reduce the ability for ticks to access your lower leg.

 Thoroughly examine your body for ticks when returning from field. If a tick is

found, fully remove it using tweezers or fingernails. Do not use petroleum or try to

burn the tick off. Save the tick for confirmation of Lyme disease. Monitor the area

on body where tick was attached, watching for irritation or rash. If rash or flu-like

symptoms develop, visit a doctor and inform him or her of tick bite.

g. Sun exposure  Use sun screen on exposed skin to prevent sunburn and skin damage. Know the

signs and symptoms of heat exhaustion and heat stroke. Wear sunglasses and

use sunscreen. Drink enough water to keep hydrated.

h. Altitude problems  Headache, shortness of breath, trouble sleeping, and dizziness. Drink more water

than usual and reduce salty food intake.

i. Waders and wading boots  Only wear waders that are the correct size for your feet and body. Nylon breathable waders are adaptable to a wide variety of temperatures and conditions, and

they are essential. Supportive wading boots are essential and give the traction

and support necessary for stream work. Wading boots will be worn any time

biological technicians are in streams.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 75

10. Encountering hazardous situations a. Threatening individuals  Use positive communication and conflict management behaviors in early stages

of conflict situations to prevent or diffuse low-level hostile behavior.

 If threatened in any way by members of the public, withdraw and report the

incident to your supervisor.

 Always attain the landowner’s permission before entering private property.

b. Illegal activities  Leave the area immediately if you feel unsafe because of illegal activity.

 If an area appears to be used for illegal activities, such as a marijuana garden or

methamphetamine lab, leave the area immediately by the same route taken to

enter the area.

 Report suspicious activity to your supervisor.

 Always attain the landowner’s permission before entering private property.

c. Wild animals such as black bears,

wolves, bison, elk, deer, moose,

bobcats, poisionus snakes, feral

swine, etc.

 Make noise by talking loudly or using a noisemaker such as a bell or whistle to

reduce the chances of surprising an animal.

 Immediately leave the area by backtracking if you encounter any animal that

appears injured or sick, or may be feeding, mating, or have young nearby. Report

the incident to the proper authorities if the animal acted aggressively without

provocation.

 Learn the appropriate actions to take if you are approached by any of the animals

that may inhabit your work location. These actions differ depending on the type

of animal.

 Learn to identify dangerous animals in your working area and never harrass or

provoke wildlife.

 Avoid walking blindly through thick vegetation by using a stick or pole in front of

you to part the brush or grass.

 In areas with poisonous snakes, tap the ground in front of you with a pole or stick

as you walk to help you see snakes before you get too close.

 Wear snake-proof chaps when appropriate.

d. Domestic animals such as dogs,

cattle, swine, etc.

 If an animal is acting aggressive or skittish, stay in the vehicle and wait for the

landowner to come outside. Honk your horn if necessary to alert the landowner

that you are there.

 Ask landowners over the phone about the location of potentially dangerous

domestic animals and request that they be moved or tied up while you are visiting

the location, or plan to visit when the animal will not be there.

 Make sure that landowners know when you are working in the area if you believe

they may have an aggressive or protective animal.

e. Hazardous materials  Whenever encountering containers of unidentified liquids or powders, stay clear

of the site. Do not walk into or touch spilled material. Avoid inhalation of fumes,

smoke, and vapors, even if no hazardous materials are known to be involved.

Do not assume that gases or vapors are harmless because they do not smell.

Odorless gases or vapors may be harmful. Drums may contain toxic materials,

leak, and contaminate their immediate surroundings.

 If it is possible to read any labels without risk of contaminating yourself, do so

and write the information down. Note location, time of encounter, and any other

pertinent information. Then report it to supervisor.

 Likely areas where hazardous materials are encountered include abandoned

mine sites, old construction sites, and old homestead sites.

f. Encountering hunters  Plan field work appropriately given area hunting use and seasons.

 Wear blaze orange vest or clothing.

 Ensure landowners know where you will be and when you will be there.

 Inform hunters of where you will be and how long you expect to be there, and

find out where they plan to hunt.

 If someone is hunting near your plot and is there first, return at a later date.

10. LINE OFFICER SIGNATURE 11. TITLE 12. DATE
76 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

JHA Instructions (References-FSH 6709.11 and .12)

The JHA shall identify the location of the work project or activity, the name

of employee(s) involved in the process, the date(s) of acknowledgment, and

the name of the appropriate line officer approving the JHA. The line officer

acknowledges that employees have read and understand the contents, have

received the required training, and are qualified to perform the work project or

activity.

Blocks 1, 2, 3, 4, 5, and 6: Self-explanatory.

Block 7:	 Identify all tasks and procedures associated with the work project

or activity that have potential to cause injury or illness to personnel

and damage to property or material. Include emergency evacuation

procedures (EEP).

Block 8:	 Identify all known or suspect hazards associated with each respective

task/procedure listed in block 7. For example—

a. Research past accidents/incidents.

b. Research the Health and Safety Code, FSH 6709.11, or other

appropriate literature.

c. Discuss the work project/activity with participants.

d. Observe the work project/activity.

e. A combination of the above.

Block 9:	 Identify appropriate actions to reduce or eliminate the hazards identified in block 8. Abatement measures listed below are in the order of

the preferred abatement method:

a. Engineering controls (the most desirable method of abatement). For

example, ergonomically designed tools, equipment, and furniture.

b. Substitution. For example, switching to high flashpoint, nontoxic

solvents.

c. Administrative controls. For example, limiting exposure by reducing

the work schedule and establishing appropriate procedures and

practices.

d. Personal protective equipment (PPE) (least desirable method of

abatement). For example, using hearing protection when working

with or close to portable machines (chain saws, rock drills, and

portable water pumps).

e. A combination of the above.

Block 10:	 The JHA must be reviewed and approved by a line officer. Attach a

copy of the JHA as justification for purchase orders when procuring

PPE.

Blocks 11 and 12: Self-explanatory.

EEP Instructions (Reference FSH 6709.11)

Work supervisors and crew members are responsible for developing and

discussing field EEP and alternatives in the event a person becomes seriously ill

or injured at the worksite.

Be prepared to provide the following information:

a. Nature of the accident or injury (avoid using victim’s name).

b. Type of assistance needed, if any (ground, air, or water evacuation).

c. Location of accident or injury, best access route into the worksite (road name

or number), identifiable ground and air landmarks.

d. Radio frequencies.

e. Contact person.

f. Local hazards to ground or aviation vehicles.

g. Weather conditions (wind speed and direction, visibility, and temperature).

h. Topography.

i. Number of individuals to be transported.

j. Estimated weight of individuals for air or water evacuation.

The items listed above serve only as guidelines for the development of EEPs.

JHA and Emergency Evacuation Procedures Acknowledgment

We, the undersigned work leader and crew members, acknowledge participation

in the development of this JHA (as applicable) and accompanying EEPs. We

have thoroughly discussed and understand the provisions of each of these

documents:

	 SIGNATURE DATE	 SIGNATURE DATE
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 77

Appendix 3. Field Forms 

List of Acronyms

GDE = Groundwater-dependent ecosystems

FS = Forest Service

ID = Identification

LOV in FG = List of values in field guide

NRM-Infra = Natural Resource Manager-Infrastructure

HUC = hydrologic unit code

USGS = U.S. Geological Survey

LRR = Land Resource Region

MLRA = Major Land Resource Area

UTM = Universal Transverse Mercator

UOM = Unit of measure

F = Fahrenheit

C = Celsius

GPS = Global Positioning System

NAD = North American Datum

WGS = World Geodetic System

HCL = hydrochloric acid

mv = millivolts

mg/L = milligrams per liter

(mS/cm) = microsiemens/centimeter

ORP = Oxidation-reduction potential

DO = dissolved oxygen

ATV = All-terrain vehicle

SOI = Species of interest

TES = Threatened and endangered species

SOC = Species of concern

DBH = Diameter at breast height
78 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Pre-Field Survey (this site information is compiled prior to field visit and updated in the field as necessary) 

Site ID ________________________________________ Project Name _________________________________ 

Purpose(s) (LOV in FG)_______________________________State(s) ___________________________________ 

County(s) __________________ Land Status(’s) ____________________ FS Region(s) _____________________ 

FS Forest/Grassland/Prairie(s) _________________________ FS District(s) _____________________________ 

Grazing Allotment Number _______________________ Grazing Allotment Name ________________________ 

NRM-Infra Reference Number _________________________________________________________________ 

Water Right Number _____________________________ Water Right Status ____________________________ 

HUC(s)(12-digits) ______________________________ Ecological Unit ________________________________ 

Ecological System (LOV in FG appendix) _________________________________________________________ 

Local Feature-Type Name _____________________________________________________________________ 

...................................................................................................................................... 

USGS Quad _______________________________________ Magnetic Declination _______________________ 

Geologic Map Name _____________________________ Geologic Map Unit ____________________________ 

Land Resource Region (LRR) and MLRA __________________________________________________________ 

Soil Map Name _________________________________ Soil Map Unit ________________________________ 

...................................................................................................................................... 

Information to help arrive at site, which will also be recorded in the field (on Field Survey Activities form) 

UTM coordinates: Zone __________________ Easting __________________ Northing __________________ 

Latitude Degrees ____________________ Minutes ____________________ Seconds ____________________ 

Longitude Degrees ____________________ Minutes ____________________ Seconds ___________________ 

Latitude Decimal Degree _______________________ Longitude Decimal Degree ________________________ 

Horizontal Datum ____________________________ Elevation ________________ UOM ________________ 

...................................................................................................................................... 

Location—Driving route _____________________________________________________________________ 

_________________________________________________________________________________________ 

_________________________________________________________________________________________ 

Location—Hiking route ______________________________________________________________________ 

_________________________________________________________________________________________ 

_________________________________________________________________________________________ 

Location—Other ___________________________________________________________________________ 

...................................................................................................................................... 

Preliminary GDE Type(s) ____________________________________________________________________ 

Determination Source _______________________________________________________________________ 

Archeological, Paleontological, Cultural, or Historic Sites or Use _______________________________________ 

_________________________________________________________________________________________ 

Available Data (other sources) _________________________________________________________________ 

Site and Geographic (p. 13) Mapping (p. 16) Route (p. 17) Other (p. 17) 

(Word and PDF files are available from the Forest Service Washington Office Groundwater Program.)
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 79

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Weather (select 1) 

� Recent rain 

� Rain during survey 

� Snowfall, hail, sleet during survey

� Snow on ground 

� No current/recent precipitation 

Relative Area of GDE 

____ % Spring emergence 

____ % Channel 

____ % Wetland/Riparian 

____ % Open water 

____ % Other or unknown 

Horizontal Datum (select 1) 

� NAD-27 

� NAD-83 (recommended) 

� WGS-72 

� WGS-84 

Geologic Structure Type 

(select 1) 

� Bedding 

� Contact 

� Fault 

� Fracture 

� Lineation 

� Conduit 

� Unknown 

Determined by 

� Observation 

� Geologic Map 

� Other: 

Field Survey Activities 

Site ID _______________________________________________________ 

Survey Date __________________ Time Start __________ End __________ 

Examiners ____________________________________________________ 

Air Temp (UOM: F or C) ______ Area of GDE (and UOM) ______ 

Area Determined by (LOV in FG) ___________________________ 

Area Sampled, If Site Divided _______________________________ 

Reference Point (briefly describe) ____________________________ 

_______________________________________________________ 

Compass Bearing Long Axis _______ Magnetic __ or True North __ 

If True, Declination _________________ 

Transect Interval (table at right) ________ 

Slope (%) ______ Aspect (degrees) ______ 

Surrounding Vegetation (LOV in FG) 

_____________________________ 

Cut- level for plants (LOV in FG) 

__________________________ 

......................................................................................................................................... 

GPS Make & Model ___________________ GPS Accuracy ______________ 

UTM Zone ______ Easting ________________ Northing _______________ 

Latitude Degrees ___________ Minutes ____________ Seconds __________ 

Longitude Degrees ___________ Minutes ___________ Seconds __________ 

Latitude Decimal Degree ________________________ Longitude Decimal Degree ________________________ 

Elevation _____________ UOM _________ Determined by (circle 1) GPS; Topo Map; Other _____________ 

........................................................................................................................................ 

Evidence of Groundwater (LOV in FG) _________________________________ 

GDE Type, primary _________________________________________________ 

GDE Type, secondary(s) _____________________________________________ 

Surficial Material, primary (LOV in FG) _________________________________ 

Surficial Material, secondary(s) (LOV in FG) ______________________________ 

Lithology, primary (LOV in FG) _______________________________________ 

Is primary lithology also groundwater source aquifer (circle 1): Yes No Unknown 

Level of certainty (circle 1): Known Assumed Unknown 

Lithology, secondary (LOV in FG appendix) ______________________________ 

Landform, primary (LOV in FG appendix) _______________________________ 

Landform, secondary (LOV in FG appendix) _____________________________ 

Geology Notes _____________________________________________________________________________ 

Size of GDE 

(m2) 

Transect 

Interval (m) 

Quadrat 

Interval (m) 

< 20 2 1 2 

20 to 40 2 2 

40 to 80 3 2 

80 to 150 3 2 

150 to 250 4 3 

250 to 500 5 4 

500 to 750 6 5 

750 to 1,000 7 6 

1,000 to 1,500 8 7 

1,500 to 2,500 10 9 

2,500 to 4,000 12 10 

4,000 to 6,000 16 12 

6,000 to 8,000 18 14 

8,000 to 10,000 20 16 

> 10,000 divide into smaller units 

Survey Information (p. 19) Geologic Setting (p. 23) Georeferencing (p. 22) 
80 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Photos (p. 26)

One photo can represent multiple things, as long as they are all noted in “Location” below.

Camera

Photo 

Number Location (from list above or other)

Notes (light, distance to camera, 

objects, etc.)

� Spring source (if applicable) 

For springs with outflow channels: 

o Looking downstream, standing at/near source 

o Looking upstream/uphill, standing at/near source 

� Overview, from a hill (if possible) 

Locations to take photos: 

� Reference point 

� Each transect, from starting point 

� Center of site 

� Water measurement locations 

� Soil hole locations 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 81

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Site Sketch Map (p. 27)

To include on map: 

� Reference point 

� Approximate locations/dimensions of major 

geomorphic surfaces 

� Springs: 

o Spring source 

o Channel locations 

o Structures including spring boxes, troughs, 

and pipelines 

o Pool location, if limnocrene 

� Areas of standing water (indicate deepest part) 

� Location of measurements: 

o Transects 

o Soil holes 

o Water table measurement locations 

o Wells/piezometers 

o Water quality samples 

� Structures or other human-made features 

� Indication of North (true recommended, or magnetic) 

� Indication of scale 

� Boundaries of GDE or area sampled 
82 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Vegetation Quadrats (p. 30) multiple copies of this sheet will be needed 

Reminders: Transect bearing _____ Transect interval _____ Quadrat interval _____ UOM ____ Cut-level ____ 

Transect Number

Quadrat Distance 

Setting

Record value 1 – 4 

(quadrat sum must be 4)

Bare soil

Gravel

Cobble

Stone

Boulder

Bedrock

Basal vegetation

Litter

Bryophyte

Water

Wood

Bryophyte cover

Species Cover

Note: UOM = unit of measure; LOV in FG = list of values in field guide 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 83

Forest Service GDE Level II Inventory

Line Intercept for Woody Cover (p. 33) multiple copies of this sheet may be needed if many 

woody plants 

Tape UOM (ft or m) _________ 

Transect 

Number Species

Canopy 

Start

Canopy 

End 

Transect End 

(record once 

per transect)

 
84 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Trees (p. 34) multiple copies of this sheet may be needed if there are many trees 

Tape UOM (ft or m) _________ 

Transect 

Number

Distance 

Along 

Transect Species

Live or 

Dead

DBH 

(UOM _____ )
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 85

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Additional Plant Species (p. 34)

In particular look for threatened or endangered species and invasive species. 

Species Setting Comment

Plant Specimens (p. 35)

Species or Unknown Code Brief Description
86 Groundwater-Dependent Ecosystems: Level II Inventory Field Guid

e

Forest Service GDE Level II Inventory

Site Name _Recorder __

Soil (p. 36)Method of soil extraction _________________________________ 

Location: 

Unbiased 

(Transect and 

Distance); or 

Targeted

Depth of Peat, 

Mucky Peat and 

Muck (such as 8 

cm to 17 cm) 

(and UOM)

Depth to 

Mineral Layer 

(and UOM)

Texture of 

Mineral Layer

Color of 

Mineral Soil

Redoximorphic 

Features and 

Depths (and 

UOM)

Hydrogen 

Sulfide 

Odor

Reaction 

to Dilute 

HCL

Depth o

Hole (an

UOM) 

Fen Characteristics (p. 39)Yes, fen characteristics observed or No, fen characteristics not observed Comments ________________Yes, histosol or histic epipedon observed or No, histosol or histic epipedon not observed Comments ________________
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 87

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Water Table Type (select 1) 

� Apparent 

� Artesian 

� Ponding 

� Unknown 

� Other: 

Flow Patterns for Site 

 Inflow (select 1; LOV in FG): 

________________________ 

Outflow (select 1; LOV in FG): 

________________________ 

Surface Water (multiple ok) 

� No standing or flowing water 

visible 

� Patches of standing water 

� Extensive standing water 

� Flowing water in channels 

Hydrology (p. 40)

Location: 

Transect or 

Other

Location: 

Distance or 

Other

Source of Water 

Table 

Measurement

Hole Depth 

(and UOM)

Water Table Depth 

(and UOM)

Dry 

(yes or no)

 ..............................................................................................

....................................... 

 

Site Flow Estimate: ______________________________ Comment: ____________________________________ 

Reason if no flow measurement (circle 1): Diffuse flow; No outflow; Not a spring; Spring is dry; Other _________ 

Hydroperiod (LOV in FG) ___________________ Length of Outflow Stream (LOV in FG) __________________ 

What Happens to Stream Outflow (LOV in FG) _____________________________________________________ 

......................................................................................................................................... 

Location: Transect

& Distance; or 

Targeted (describe)

Time of 

Day 

Temperature 

(UOM: F or 

C) Water pH

Specific 

Conductance 

(μS/cm) ORP (mV) DO (mg/L)

Location of Flow 

Measurement Flow Method 

Flow 

Instrument Flow (and UOM)

Percent 

Captured Comments

 

 

 

 

Flow and Spring Channel (p. 42) Water Quality (p. 44) Water Table (p. 40) 
88 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Fauna (p. 46)

Includes aquatic vertebrates, terrestrial herpetofauna, terrestrial vertebrates, and aquatic macroinvertebrates 

Search Methods (describe each) ______________________________________________________________________ 

Time or Effort Spent Searching ______________________________________________________________________ 

Species

Setting (type of 

substrate, water, 

etc.)

Detection Type 

(visual, capture 

[such as net], 

audible, etc.)

Number of 

Individuals

Age or Size 

Info

Specimen 

Label/Code
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 89

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Hydrologic Alteration (multiple ok) 

� Water diversion (permanently diverted) 

� Water diversion (water eventually returns to site) 

� Upgradient extraction of surface water or 

groundwater (prespring emergence) 

� Downgradient capture of surface water or 

groundwater (post-spring emergence) 

� Extraction of water within a wetland 

� Extraction of water at spring source 

� Regulated water flow by impoundment/dam 

� Pollution 

� Flooding 

� Wells 

� None observed 

� Other: _______________________________ 

Diverted Volume __________ UOM _______ 

Percent Diverted __________ 

Soil Alteration (multiple ok) 

� Channel erosion 

� Compaction 

� Debris flow 

� Deposition 

� Displacement of soil 

� Erosion (general) 

� Evaporate deposition 

� Excavation 

� Ground disturbance (general) 

� Gully erosion 

� Mass wasting 

� Mining 

� Pedestals or hummocks (by people or animals) 

� Pedestals (small-scale, rain-splash induced) 

� Pipes 

� Rill erosion 

� Ruts (from vehicle tread) 

� Sheet erosion 

� Slump 

� Splash erosion/ soil crust 

� Wind erosion 

� Soil mixing/churning 

� Soil removal (peat mining) 

� Trails (by people or animals) 

� None observed 

� Other: _______________________________ 

Structures (multiple ok) 

� Buried utility corridors 

� Enclosure (such as spring house, spring box or 

concrete enclosure) 

� Erosion control structure 

� Exclosure fence 

� Oil and gas well 

� Pipeline 

� Point source pollution 

� Power lines 

� Road (includes construction and maintenance) 

� None observed 

� Other: _______________________________ 

Recreational Effects (multiple ok) 

� Camp sites 

� Tracks or trails by vehicles (ATV, 4-wheel drive, 

etc.) 

� None observed 

� Other: _______________________________ 

Animal Effects (multiple ok) 

� Beaver activity 

� Feral animals 

� Grazing or browsing (by ungulates) 

� Wild animals 

� Livestock 

� Trails by animals and people 

� Trampling (by ungulates, native or nonnative) 

� None observed 

� Other: _______________________________ 

Miscellaneous (multiple ok) 

� Fire 

� Tree cutting (timber harvest or other) 

� Refuse disposal 

� None observed 

� Other: _______________________________ 

Disturbance (p. 50)

Archeological, Paleontological, Cultural, Historic Sites/Use 

____________________________________________ 

____________________________________________ 

____________________________________________ 
90 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Management Indicator Tool (p. 52)

Management Indicators

True

(Yes)

False

(No)

Does

Not

Apply

Unable

To

Assess Comment

Hydrology

1. Aquifer Functionality: No evidence suggests 

that the aquifer supplying groundwater to 

the site is being affected by groundwater 

withdrawal or loss of recharge.

 

2. Watershed Functionality: Within the 

watershed, no evidence suggests 

upstream/upgradient hydrologic alteration 

that could adversely affect the GDE site.

 

3. Water Quality: Changes in water quality 

(surface or subsurface) are not affecting the 

groundwater dependent ecosystem site.

 

Geomorphology and Soils

4. Landform Stability: No evidence indicates 

human-caused mass movement or other 

surface disturbance affecting the GDE site 

stability.

 

5. Runout Channel: The channel, if present, is 

functioning naturally and is not entrenched, 

eroded, or otherwise substantially altered.

 

6. Soil Integrity: Soils are intact and functional. 

For example, saturation is sufficient to 

maintain hydric soils, if present; there is not 

excessive erosion or deposition.

 

Biology

7. Vegetation Composition: The site includes 

anticipated cover of plant species associated 

with the site environment, and no evidence 

suggests that upland species are replacing 

hydric species.

 

8. Vegetation Condition: Vegetation exhibits 

seasonally appropriate health and vigor.

 

9. TES, SOI/SOC, Focal Floral Species:

Anticipated floral species are present (will 

vary by ecological region and will require 

some baseline information).

 

10. Faunal Species: Anticipated aquatic and 

terrestrial faunal species associated with the 

site environment are present. 

 

11. TES, SOI/SOC, Focal Faunal Species:

Anticipated faunal species are present (will 

vary by ecological region and will require 

some baseline information).

 

12. Invasive Species: Invasive floral and faunal 

species are not established at the site. 

 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 91

Forest Service GDE Level II Inventory

Site Name ___________________ 

Recorder ____________________ 

Page _____ of _____ 

Management Indicators

True

(Yes)

False

(No)

Does

Not

Apply

Unable

To

Assess Comment

Disturbances

13. Flow Regulation: Flow regulation is not 

adversely affecting the site.

 

14. Construction and Road Effects: Construction, 

reconstruction, or maintenance of physical 

improvements, including roads, is not adversely 

affecting the site.

 

15. Fencing Effects: Protection fencing and 

exclosures are appropriate and functional.

 

16. Herbivore Effects: Herbivory is not adversely 

affecting the site.

 

17. Recreational Effects: Recreational uses, 

including trails, are not adversely affecting the 

site.

 

18. Other Disturbance Effects: Wildland fire, insect, 

disease, wind throw, avalanches, or other 

disturbances are not adversely affecting the site.

 

Administrative Context

19. Cultural Values: Archaeological, historical, or 

tribal values will not affect inventory, 

restoration, use, or management of this site. 

 

20. Land Ownership: The entire site and immediate 

area is under the jurisdiction and management 

of the Forest Service.

 

21. Other Landowner Actions: Activities or 

management on lands outside Forest Service 

jurisdiction are not adversely affecting the site.

 

22. Land Management Plan: The land and resource 

management Plan provides for effective site 

protection.

 

23. Environmental Compliance: Authorized and 

administrative uses are in compliance and are 

not adversely affecting the site.

 

24. Water Uses: There are no substantial water uses 

in the watershed, or in the aquifer supplying 

groundwater to the site, that could directly or 

cumulatively adversely affect the GDE.

 

25. Water Rights: Water rights have been filed for 

the site under state law or water uses exempted 

under state law are documented. Forest Service 

federal reserved rights are documented as 

appropriate. Third-party water use is in 

accordance with all elements of the water right 

or conditions of the exemption, and with the 

Forest Service authorization that allows the use.

 
92 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 93

Appendix 4. Site Protection Guidelines

This section is provided to help minimize the disturbance from 

the data-collection process by researchers, managers, and data 

collectors. The potential disturbances that can result from the 

data-collecting process include the following:

 Trailing, erosion, geomorphic alteration (from foot traffic, 

etc.). 

 Destruction or alteration of vegetation.

 Damage to peat.

 Soil compaction and altered soil-water storage.

 Hydrologic alteration from water measurement activities 

(wells, etc.).

 Spread of invasive species (by data collectors or managers).

To prevent damage to sites, please follow these guidelines.

Minimize

 Number of people who visit the site.

 Duration of visits.

 Frequency of visits.

 Walking on the site.

 Digging holes.

 Destructive sampling.

 Collecting plant or animal specimens.

 Bringing heavy equipment to the site.

 Placing heavy gear on wet areas.

 Using unsterilized equipment (nets, etc.).

Pre-Site Visit

 Decontaminate shoes/boots and equipment that will be 

brought to the site to prevent importing invasive species or 

disease.

 Plan the visit to use the time wisely and to minimize the 

amount of walking on the site.

During the Site Visit

 Set equipment, especially heavy items, outside wet areas (in 

uplands).

 Consider taking pictures, or recording observations, instead 

of collecting specimens.

 Sit, eat lunch, etc., outside the wet area.

 Walk around the groundwater-dependent ecosystem site, 

rather than through it, as much as possible.

 Do multiple things on each trip through the site to minimize 

trampling.

 Place temporary wood planks on walking paths to avoid 

creating ruts that redirect and channelize water.

Post-Site Visit—Decontamination

At the end of each site visit, to prevent the spread of invasive 

species, decontaminate shoes/boots, waders, and all equipment 

used at the site. If you do not know if the decontamination was 

done after the last visit, then follow these procedures before a 

field visit:

1. Use a scrub brush (tooth brush for small equipment) and 

water to remove all visible mud, vegetation, and other 

material. 

2. Dry the boots and equipment.

3. Soak boots in a Clorox solution or some other solution (such 

as Sparquat or 409) depending on the regional invasive 

species of concern. 

4. Rinse with water (distilled for equipment).

5. Allow boots and equipment to air dry (in the sun works 

best).
94 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 95

Appendix 5. Groundwater-Dependent Ecological Systems Described 

in NatureServe

The following table lists Ecological Systems from NatureServe (2011) that exhibit groundwater dependency and the States where 

they are known to occur or where they potentially could occur (indicated by “?”).

Ecological system States

Fen systems

Boreal-Laurentian-Acadian Acidic Basin Fen MA, ME, MI, MN, NH, NY, VT, WI

Ozark-Ouachita Fen AR, MO

North-Central Interior Shrub-Graminoid Alkaline Fen IA, IL, IN, MI, MN, ND, OH, PA, SD, WI

Interior Low Plateau Seepage Fen KY, OH?, TN

Southern and Central Appalachian Bog and Fen GA, KY, NC, SC, TN, VA

Mediterranean California Serpentine Fen CA, OR

North-Central Appalachian Seepage Fen CT, MA, MD, NJ, NY, PA, VA, VT, WV

North Pacific Bog and Fen AK, OR, WA

Mediterranean California Subalpine-Montane Fen CA, NV, OR

Rocky Mountain Subalpine-Montane Fen AZ, CO, ID, MT, NV, OR, UT, WA, WY

Laurentian-Acadian Alkaline Fen MA, ME, MI, MN, NH, NY, PA, VT, WI

West Gulf Coastal Plain Herbaceous Seepage Bog AR?, LA, TX

Southern Coastal Plain Herbaceous Seep and Bog AL, FL, LA, MS

East Gulf Coastal Plain Interior Shrub Bog AL, GA, MS

North-Central Interior and Appalachian Acidic Peatland CT, IL, IN, MA, ME, MI, MN, NH, NJ, NY, OH, PA, RI, VT, WI

Southern Ridge and Valley Seepage Fen AL, GA

Western North American Boreal Herbaceous Fen AK

Alaskan Pacific Maritime Fen and Wet Meadow AK

Western North American Boreal Black Spruce-Tamarack Fen AK

Boreal-Laurentian Conifer Acidic Swamp and Treed Poor Fen ME, MI, MN, NH, NY, VT, WI

Swamp systems

Atlantic Coastal Plain Streamhead Seepage Swamp, Pocosin, and Baygall FL, GA, NC, SC, VA

East Gulf Coastal Plain Northern Seepage Swamp AL, IL, KY, MS, TN

Laurentian-Acadian Alkaline Conifer-Hardwood Swamp CT, ME, MI, MN, NY, VT, WI

North Pacific Hardwood-Conifer Swamp AK, OR, WA

North Pacific Shrub Swamp AK, OR, WA

North-Central Appalachian Acidic Swamp CT, MA, MD, NH, NJ, NY, OH, PA, RI, VA, VT

North-Central Interior Wet Meadow-Shrub Swamp IA, IL, IN, MI, MN, MO, ND, OH, SD, WI

North-Central Interior and Appalachian Rich Swamp CT, DE, IL, IN, MA, MD, MI, MN, NJ, NY, OH, PA, RI, VT, WI

Northern Appalachian-Acadian Conifer-Hardwood Acidic Swamp CT, MA, ME, NH, NY, PA, VT

Northern Rocky Mountain Conifer Swamp ID, MT, OR, WA, WY

Southern Coastal Plain Nonriverine Basin Swamp AL, FL, GA, LA?, MS, SC

Southern Coastal Plain Seepage Swamp and Baygall AL, FL, GA, LA, MS

West Gulf Coastal Plain Seepage Swamp and Baygall AR, LA, OK, TX

Acadian-Appalachian Conifer Seepage Forest ME, NH, NY, VT

Cumberland Seepage Forest AL, KY, TN, WV

Central Atlantic Coastal Plain Nonriverine Swamp and Wet Hardwood Forest GA, NC, SC, VA

Mediterranean California Serpentine Foothill and Lower Montane Riparian

Woodland and Seep

CA, OR

Interior Highlands Forested Acidic Seep AR, MO?, OK?

Central Florida Wet Prairie and Herbaceous Seep FL

Atlantic Coastal Plain Sandhill Seep GA, NC, SC

Piedmont Seepage Wetland AL, GA, NC, SC, VA?

High Allegheny Wetland MD, PA, WV

Southern Appalachian Seepage Wetland GA, KY, NC, SC, TN, VA
96 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Ecological system States

Marsh systems

North American Arid West Emergent Marsh AZ, CA, CO, ID, MT, NM, NV, OR, TX, UT, WA, WY

Eastern Great Plains Wet Meadow, Prairie, and Marsh IA, IL, KS, MN, MO, ND, NE, OK, SD, TX?

Northern Great Lakes Coastal Marsh MI, WI

Temperate Pacific Freshwater Emergent Marsh AK, CA, OR, WA

Western Great Plains Open Freshwater Depression Wetland KS, MT, ND, NE, OK, SD, TX, WY

Other systems

North Pacific Coastal Interdunal Wetland AK, OR, WA

Mediterranean California Coastal Interdunal Wetland CA, OR

Rocky Mountain Alpine-Montane Wet Meadow AZ, CO, ID, MT, NM, NV, OR, SD, UT, WA, WY

Temperate Pacific Subalpine-Montane Wet Meadow CA, NV, OR, WA

Colorado Plateau Hanging Garden AZ, CO, NV?, UT

Southern Coastal Plain Spring-Run Stream Aquatic Vegetation FL, GA
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 97

Appendix 6. Equipment List

 Field Forms (appendix 3).

 Clipboard.

 Electronic data recorder (personal digital assistant, etc.)—if 

available.

 Pencils. 

 Notebook or paper (waterproof).

 Graph paper (for sketch map).

 Calculator.

 Topographic map of site. 

 Aerial photograph of site.

 GPS (Global Positioning System) unit.

 Compass.

 Clinometer. 

 Watch, stopwatch, or other timer.

 Photography.

§ Camera (digital is recommended, with extra memory 

and batteries). 

§ Photo scale.

§ Board or card for identifying photo location.

 Measurement. 

§ 100- and/or 50-meter tapes. Bring three tapes if possible. Metric is highly recommended. English unit tapes 

are discouraged because data will have to be converted 

to metric before being entered into database.

§ Measuring staff, 1.5 meters (also listed under Vegetation).

§ Metric ruler.

§ Laser rangefinder.

 Water quality. 

§ Temperature probe. 

§ pH probe. 

§ Oxidation-reduction potential (ORP) probe or dissolved 

oxygen (DO) probe. 

§ Water conductivity probe. 

§ Spare probes (temperature, pH, DO, ORP, and conductivity) and cable.

 Flow measurement (one or more of following).

§ Weir plate (and bubble level).

§ Current meter.

§ Flume (and bubble level).

§ Volumetric container(s).

§ Float (flagging, float device).

§ Current meter.

§ Wading rod. 

§ Headphones or velocimeter.

§ Short pipe (for concentrating and measuring low flows).

 For established monitoring wells.

§ Water-level meter with electrical tape.

§ Bailer and rope. 

 Soil/subsurface.

§ Shovel, spade, auger, and/or push probe with clean-out 

tool. 

§ Soil knife/trowel.

§ Hand lens (10x or combination lenses).

§ pH kit.

§ Soil description sheets.

§ Water/spray bottle.

§ Soil color book (Munsell color chart with gley color 

plates).

§ Dilute hydrochloric acid (HCl) with dropper.

§ Sample bags.

§ Local soil survey.

§ Bailing can—where groundwater can fill soil pits.

 Vegetation.

§ Quadrat frame (0.5 x 0.5 meters).

§ Pin flags.

§ Plant press (with cardboard, newspaper, and felt).
98 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

§ Plant lists and identification resources for region, 

including:

" Invasive species list—Can be obtained for the 

appropriate State on line at http://plants.usda.gov/

java/noxiousDriver. Forest Service personnel can 

download/export the invasive plant lists for any forest unit by either (1) using the Forest Service Plant 

List Wizard in I-Web or (2) using the Geospatial 

Interface queries in ArcMap.

" Management indicator or sensitive species list.

" Species of concern or species of interest or focal 

species lists.

§ Sample bags.

§ Digging tool (could be same as for soil sampling).

§ Diameter tape (for diameter at breast height).

§ Compass.

§ Measuring staff, 1.5 meters (also listed under Measurement).

 Fauna.

§ Animal lists and identification resources for region.

§ Binoculars (for observing birds and other wildlife, or 

plants on cliff wall).

§ Aquatic macroinvertebrate and vertebrate sampling 

tools.

" Net (mesh size should not exceed 250 microns).

· Kick net (0.09 square meter area).

· D-frame net (35- to 45-centimeter diameter, 

D-shaped frame with a 0.2-millimeter mesh net).

· Hand net or aquarium net (4-inch or 6-inch with 

square frame, 15.2- to 25.6-centimeter long 

sides, and 250 micron mesh net).

" 90-percent Ethanol (EtOH) (preservative).

" Plastic bottles (250 milliliters).

" Waterproof labels for bottles include sample date, 

field note number, lead surveyor, sample location 

(State, county, township/range/quarter-section 

coordinates, and Universal Transverse Mercators), 

and spring name.

" Buckets.

" White bottom pan (useful for identifying invertebrates in the field). 

" Formalin. 

" Beating sheet, aerial net, forceps, acetate envelopes.

 Decontamination materials/supplies.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 99

Appendix 7. Secondary Lithology

Secondary code Primary lithology Secondary lithology

ANBA Igneous extrusive Analcite basalt

ANDE Igneous extrusive Andesite

ANPO Igneous extrusive Andesite porphyry

BASA Igneous extrusive Basalt

BAPO Igneous extrusive Basalt porphyry

BAAN Igneous extrusive Basaltic andesite

BASN Igneous extrusive Basanite

DACI Igneous extrusive Dacite

DAPO Igneous extrusive Dacite porphyry

FELS Igneous extrusive Felsite

LATI Igneous extrusive Latite

LAPO Igneous extrusive Latite porphyry

LEBA Igneous extrusive Leucite dasanite

LEPH Igneous extrusive Leucite phonolite

LETE Igneous extrusive Leucite tephrite

LIMB Igneous extrusive Limburgite

LIPO Igneous extrusive Limburgite porphyry

MELI Igneous extrusive Melilitite

NELA Igneous extrusive Nepheline latite

NELAPO Igneous extrusive Nepheline latite porphyry

NEPH Igneous extrusive Nephelinite

OBSI Igneous extrusive Obsidian

OCEA Igneous extrusive Oceanite

OLBA Igneous extrusive Olivine basalt

OLNE Igneous extrusive Olivine nephelinite

PERL Igneous extrusive Perlite

PHON Igneous extrusive Phonolite

PHPO Igneous extrusive Phonolite porphyry

PITC Igneous extrusive Pitchstone

PUMI Igneous extrusive Pumice

QUBA Igneous extrusive Quartz basalt

QULA Igneous extrusive Quartz latite

QULAPO Igneous extrusive Quartz latite porphyry

RHYO Igneous extrusive Rhyolite

RHPO Igneous extrusive Rhyolite porphyry

SCOR Igneous extrusive Scoria

TEPR Igneous extrusive Tephrite

TEPO Igneous extrusive Tephrite porphyry

TING Igneous extrusive Tinguaite

TRAC Igneous extrusive Trachyte

TRPO Igneous extrusive Trachyte porphyry

TRAP Igneous extrusive Trap

VITR Igneous extrusive Vitrophyre

WYOM Igneous extrusive Wyomingite

ALSK Igneous intrusive Alaskite

ALGR Igneous intrusive Alkali granite

ALSY Igneous intrusive Alkali syenite

ANOR Igneous intrusive Anorthosite

APLI Igneous intrusive Aplite

CHAR Igneous intrusive Charnockite

DIAB Igneous intrusive Diabase

DIOR Igneous intrusive Diorite

The secondary lithology list in the following table is based on USDA Forest Service (2009).
100 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Secondary code Primary lithology Secondary lithology

DIPO Igneous intrusive Diorite porphyry

DITR Igneous intrusive Ditroite

DUNI Igneous intrusive Dunite

FERG Igneous intrusive Fergusite

FOYA Igneous intrusive Foyaite

GABB Igneous intrusive Gabbro

GAPO Igneous intrusive Gabbro porphyry

GADI Igneous intrusive Gabbro/diorite

GRAN Igneous intrusive Granite

GRPO Igneous intrusive Granite porphyry

GRAO Igneous intrusive Granodiorite

GDPO Igneous intrusive Granodiorite porphyry

GRGR Igneous intrusive Graphic granite

HARZ Igneous intrusive Harzburgite

LAMP Igneous intrusive Lamprophyre

LARV Igneous intrusive Larvikite

LESY Igneous intrusive Leucite syenite

LUXU Igneous intrusive Luxullianite

MALI Igneous intrusive Malignite

MISS Igneous intrusive Missourite

MONZ Igneous intrusive Monzonite

MOPO Igneous intrusive Monzonite porphyry

NEMO Igneous intrusive Nepheline monzonite

NEMOPO Igneous intrusive Nepheline monzonite porphyry

NESY Igneous intrusive Nepheline syenite

NESYPO Igneous intrusive Nepheline syenite porphyry

NORD Igneous intrusive Nordmarkite

NORI Igneous intrusive Norite

OLGA Igneous intrusive Olivine gabbro

PEGM Igneous intrusive Pegmattite

PERI Igneous intrusive Peridotite

PICR Igneous intrusive Picrite

PULA Igneous intrusive Pulaskite

PYRO Igneous intrusive Pyroxenite

QUDI Igneous intrusive Quartz diorite

QUDIPO Igneous intrusive Quartz diorite porphyry

QUGA Igneous intrusive Quartz gabbro

QUMO Igneous intrusive Quartz monzonite

QUMOPO Igneous intrusive Quartz monzonite porphyry

QUSY Igneous intrusive Quartz syenite

SHON Igneous intrusive Shonikite

SOSY Igneous intrusive Sodalite syenite

SYEN Igneous intrusive Syenite

SYPO Igneous intrusive Syenite porphyry

SYEO Igneous intrusive Syenodiorite

THER Igneous intrusive Theralite

THPO Igneous intrusive Theralite porphyry

TROC Igneous intrusive Troctolite

UNCO Igneous intrusive Uncompahgrite

UOLI Igneous intrusive Uolite

ACHO Metamorphic Actinolite hornfels

ACMA Metamorphic Actinolite marble

ACSC Metamorphic Actinolite schist

ACEPMA Metamorphic Actinolite-epidote marble

ALMISC Metamorphic Albite-mica schist

AMPH Metamorphic Amphibolite

AMGN Metamorphic Amphibolite gneiss
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 101

Secondary code Primary lithology Secondary lithology

ANHO Metamorphic Andalusite hornfels

ANSC Metamorphic Andalusite schist

ANSPSL Metamorphic Andalusite spotted slate

ANBIHO Metamorphic Andalusite-biotite hornfels

ANGN Metamorphic Anorthosite gneiss

ATHO Metamorphic Anthophyllite hornfels

ARGN Metamorphic Arkose gneiss

AUGN Metamorphic Augen gneiss

BIGN Metamorphic Biotite gneiss

BISPSL Metamorphic Biotite spotted slate

BICLSC Metamorphic Biotite-chlorite schist

BLSL Metamorphic Black slate

BRMA Metamorphic Brucite marble

CAHO Metamorphic Calc-silicate hornfels

CLSL Metamorphic Calcareous slate

CASC Metamorphic Calcite schist

CASL Metamorphic Carbonaceous slate

CHSC Metamorphic Chiastolite schist

CHSPSL Metamorphic Chiastolite spotted sate

CLMA Metamorphic Chlorite marble

CLSC Metamorphic Chlorite schist

CDSC Metamorphic Chloritoid schist

CHMA Metamorphic Chondrodite marble

COGN Metamorphic Conglomerate gneiss

COHO Metamorphic Cordierite hornfels

COANHO Metamorphic Cordierite-anthophyllite hornfels

CRME Metamorphic Crystalline metamorphic

DBGN Metamorphic Diabase gneiss

DIMA Metamorphic Diopside marble

DIGN Metamorphic Diorite gneiss

ECLO Metamorphic Eclogite

EPAM Metamorphic Epidote amphibolite

EPGN Metamorphic Epidote gneiss

EPHO Metamorphic Epidote hornfels

EPCHSC Metamorphic Epidote-chlorite schist

FLCO Metamorphic Flaser conglomerate

FLDI Metamorphic Flaser diorite

FLGR Metamorphic Flaser granite

GBGN Metamorphic Gabbro gneiss

GABIGN Metamorphic Garnet biotite gneiss

GAGN Metamorphic Garnet gneiss

GAHO Metamorphic Garnet hornfels

GACLSC Metamorphic Garnet-chlorite schist

GAPYAM Metamorphic Garnet-pyroxene amphibolite

GLSC Metamorphic Glaucophane schist

GNEI Metamorphic Gneiss

GRGN Metamorphic Granite gneiss

GDGN Metamorphic Granodiorite gneiss

GRNO Metamorphic Granofels

GRNU Metamorphic Granulite

GRMA Metamorphic Graphite marble

GRSC Metamorphic Graphite schist

GWGN Metamorphic Graywacke gneiss

GRSL Metamorphic Green slate

GREN Metamorphic Greenschist

GREE Metamorphic Greenstone

HOBISC Metamorphic Hornblende-biotite schist

HORN Metamorphic Hornfels
102 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Secondary code Primary lithology Secondary lithology

KYHO Metamorphic Kyanite hornfels

KYSC Metamorphic Kyanite schist

MAGN Metamorphic Magnetite

MARB Metamorphic Marble

MEAR Metamorphic Meta-argillite

METC Metamorphic Metaconglomerate

METQ Metamorphic Metaquartzite

MEME Metamorphic Metasedimentary melange

METS Metamorphic Metasedimentary rocks

MSCA Metamorphic Metasedimentary alcareous

MSNC Metamorphic Metasedimentary noncalcareous

METV Metamorphic Metavolvanic rocks

MISC Metamorphic Mica schist

MIGM Metamorphic Migmatite

MOGN Metamorphic Monzonite gneiss

MYLO Metamorphic Mylonite

OLMA Metamorphic Olivine marble

PEGN Metamorphic Peridotite gneiss

PHYL Metamorphic Phyllite

PHLN Metamorphic Phyllonite

PLGN Metamorphic Plagioclase gneiss

PYSC Metamorphic Pyrophyllite schist

PRGN Metamorphic Pyroxene gneiss

PYHO Metamorphic Pyroxene hornfels

PRSC Metamorphic Pyroxene schist

QUDIGN Metamorphic Quartz diorite gneiss

QUPOGN Metamorphic Quartz porphyry gneiss

QUMISC Metamorphic Quartz-mica schist

QUSESC Metamorphic Quartz-sericite schist

QUAR Metamorphic Quartzite

QUGN Metamorphic Quartzite gneiss

RHGN Metamorphic Rhyolite gneiss

SAGN Metamorphic Sandstone gneiss

SCHI Metamorphic Schist

SCQU Metamorphic Schistose quartzite

SERP Metamorphic Serpentine

SEMA Metamorphic Serpentine marble

SEME Metamorphic Serpentine melange

SIGASC Metamorphic Sillimanite garnet schist

SIGN Metamorphic Sillimanite gneiss

SISC Metamorphic Sillimanite schist

SISL Metamorphic Silty slate

SKAR Metamorphic Skarn

SKGN Metamorphic Skarn gneiss

SLAT Metamorphic Slate

SOAP Metamorphic Soapstone

SPSL Metamorphic Spotted slate

STGN Metamorphic Staurolite gneiss

STSC Metamorphic Staurolite schist

SYGN Metamorphic Syenite gneiss

TASC Metamorphic Talc schist

TOHO Metamorphic Tourmaline hornfels

TOSC Metamorphic Tourmaline schist

TOMISC Metamorphic Tourmaline-mica schist

TRGN Metamorphic Trachyte gneiss

TRHO Metamorphic Tremolite hornfels

TRMA Metamorphic Tremolite marble

ULTR Metamorphic Ultramylonite
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 103

Secondary code Primary lithology Secondary lithology

WOHO Metamorphic Wollastonite hornfels

WOMA Metamorphic Wollastonite marble

AGGL Sedimentary Agglomerate

ANHY Sedimentary Anhydrite

ARGI Sedimentary Argillite

ARKO Sedimentary Arkose

ARAR Sedimentary Arkose argillaceous

ARCA Sedimentary Arkose calcareous

ARSI Sedimentary Arkose siliceous

ASPH Sedimentary Asphalt

BENT Sedimentary Bentonite

BREC Sedimentary Breccia

CALI Sedimentary Caliche

CHAL Sedimentary Chalk

CHER Sedimentary Chert

CHOO Sedimentary Chert oolitic

CLAS Sedimentary Claystone

CLSI Sedimentary Claystone siliceous

COAN Sedimentary Coal, anthracite

COBI Sedimentary Coal, bituminous

CONG Sedimentary Conglomerate

COQU Sedimentary Coquina

DIAT Sedimentary Diatomite

DOLO Sedimentary Dolomite

GILS Sedimentary Gilsonite

GRAY Sedimentary Graywacke

GRCA Sedimentary Graywacke calcareous

GRSA Sedimentary Greensand

GYPS Sedimentary Gypsum

HALI Sedimentary Halite

HEMA Sedimentary Hematite

INLISA Sedimentary Interbedded limestone and sandstone

INLISH Sedimentary Interbedded limestone and shale

INLISI Sedimentary Interbedded limestone and siltstone

INSASH Sedimentary Interbedded sandstone and shale

INSASI Sedimentary Interbedded sandstone and siltstone

IRON Sedimentary Ironstone

LIGN Sedimentary Lignite

LIME Sedimentary Limestone

LIAN Sedimentary Limestone arenaceous

LIAR Sedimentary Limestone argillaceous

LIBI Sedimentary Limestone bituminous

LICR Sedimentary Limestone carbonaceous

LICH Sedimentary Limestone cherty

LICL Sedimentary Limestone clastic

LIFE Sedimentary Limestone iron-rich

LIOO Sedimentary Limestone oolitic

LIOR Sedimentary Limestone organic

LIPH Sedimentary Limestone phosphatic

LISI Sedimentary Limestone siliceous

LISICL Sedimentary Limestone siliciclastic

LIMO Sedimentary Limonite

MARLST Sedimentary Marlstone

MUDS Sedimentary Mudstone

MUSI Sedimentary Mudstone siliceous

OOCA Sedimentary Oolite calcareous

OOFE Sedimentary Oolite iron-rich
104 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

Secondary code Primary lithology Secondary lithology

OOPH Sedimentary Oolite phosphatic

OOSI Sedimentary Oolite siliceous

ORTH Sedimentary Orthoquartzite

ORFS Sedimentary Orthoquartzite feldspathic

ORLI Sedimentary Orthoquartzite lithic

PHOS Sedimentary Phosphorite

PORC Sedimentary Porcellanite

RADI Sedimentary Radiolarite

ROSA Sedimentary Rock Salt

SANS Sedimentary Sandstone

SAAR Sedimentary Sandstone argillaceous

SAARFS Sedimentary Sandstone argillaceous feldspathic

SAARLI Sedimentary Sandstone argillaceous lithic

SAARQU Sedimentary Sandstone argillaceous quartz

SACA Sedimentary Sandstone calcareous

SACAFS Sedimentary Sandstone calcareous feldspathic

SACALI Sedimentary Sandstone calcareous lithic

SACAQU Sedimentary Sandstone calcareous quartz

SACRQU Sedimentary Sandstone carbonaceous quartz

SAFS Sedimentary Sandstone feldspathic

SAFE Sedimentary Sandstone iron-rich

SAFEQU Sedimentary Sandstone iron-rich quartz

SALI Sedimentary Sandstone lithic

SAQU Sedimentary Sandstone quartz

SHAL Sedimentary Shale

SHBI Sedimentary Shale bituminous

SHCA Sedimentary Shale calcareous

SHCR Sedimentary Shale carbonaceous

SHFE Sedimentary Shale iron-rich

SHPH Sedimentary Shale phosphatic

SHSI Sedimentary Shale siliceous

SIDE Sedimentary Siderite

SILS Sedimentary Siltstone

SICA Sedimentary Siltstone calcareous

SICR Sedimentary Siltstone carbonaceous

SIFE Sedimentary Siltstone iron-rich

SUBG Sedimentary Subgraywacke

SUCA Sedimentary Subgraywacke calcareous

TRAV Sedimentary Travertine

TUFA Sedimentary Tufa

TUFF Sedimentary Tuff

VOBR Sedimentary Volcanic breccia

VOLC Sedimentary Volcaniclastic

MIEXME Undifferentiated Mixed extrusive and metamorphic

MIEXSE Undifferentiated Mixed extrusive and sedimentary

MIIG Undifferentiated Mixed igneous (extrusive & intrusive)

MIIGME Undifferentiated Mixed igneous and metamorphic

MIIGSE Undifferentiated Mixed igneous and sedimentary

MIINME Undifferentiated Mixed intrusive and metamorphic

MIINSE Undifferentiated Mixed intrusive and sedimentary

MIMESE Undifferentiated Mixed metamorphic and sedimentary

ALLU Unconsolidated Alluvium

ASLO Unconsolidated Ash/loess mixture

CIND Unconsolidated Cinders

COLL Unconsolidated Colluvim

CRYO Unconsolidated Cryoturbate
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 105

Secondary code Primary lithology Secondary lithology

DIAM Unconsolidated Diamicton

DIEA Unconsolidated Diatomaceous earth

EOLI Unconsolidated Eolian deposit

GLAC Unconsolidated Glacial deposit

GLMO Unconsolidated Glacial moraine deposit

GLTI Unconsolidated Glacial till deposit

GLFL Unconsolidated Glaciofluvial deposit

GLLA Unconsolidated Glaciolacustrine deposit

GLMA Unconsolidated Glaciomarine deposit

GRSA Unconsolidated Greensand

GYSA Unconsolidated Gypsum sand

HUCA Unconsolidated Human cause/constructed

LACU Unconsolidated Lacustrine sediments

LAHA Unconsolidated Lahar

LADE Unconsolidated Landslide deposit

MARI Unconsolidated Marine sediments

MARL Unconsolidated Marl

MIXE Unconsolidated Mixed

MUCK Unconsolidated Muck

ORGA Unconsolidated Organic deposits

PEAT Unconsolidated Peat

RESI Unconsolidated Residuum

TALU Unconsolidated Talus deposit

TEPH Unconsolidated Tephra (undifferentiated)

TRAN Unconsolidated Transitional marine/continental deposits

VOAS Unconsolidated Volcanic ash

References 

U.S. Department of Agriculture (USDA), Forest Service. 2009. 

Site general: field guide. Washington, DC: U.S. Department of 

Agriculture, Forest Service, Rangeland Management Staff. 57 p.
106 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 107

Appendix 8. Landform

Geomorphic term Process/landform Code

aa flow Volcanic landform AAFL

air-fall tephra field Volcanic landform AFTF

alluvial fan Fluvial landform ALFA

anticline Tectonic landform ANTI

avalanche talus Mass wasting element landform AVTA

backshore terrace Coastal marine and lacustrine element landform BATE

badlands Landscape term and fluvial landform BADL

bajada Landscape term and fluvial landform BAJA

bald Common landform BALD

bank Fluvial landform BANK

bar Fluvial landform and microfeature BAR

bay Common landform BAY

beach Coastal marine and lacustrine landform BEAC

beach ridge Coastal marine and lacustrine element BERI

beaver Lacustrine subprocess BEAV

bench Common landform BNCH

block field Periglacial landform BLFI

blowout Common landform BLOW

caldera Volcanic landform CALD

canyon Landscape term CANY

canyonlands Landscape term CALA

Carolina Bay Coastal marine landform CABA

channel Fluvial landform and microfeature CHAN

cinder cone Volcanic landform CICO

cirque Glacial element landform CIRQ

cliff Common landform CLIF

colluvial slope Mass wasting element landform COSL

crater Volcanic landform CRAT

cuesta Fluvial landform CUES

debris flow Mass wasting landform DEFL

deflation basin Eolian landform DEBA

delta Fluvial landform and landscape term DELT

depositional stream terrace Fluvial landform DEST

depression Common landform DEPR

dike Landform DIKE

drainage channel (undifferentiated) Glacial element landform DRCH

draw Common landform DRAW

drumlin Glacial landform DRUM

earth flow Mass wasting landform EAFL

erosional stream terrace Fluvial landform ERST

escarpment Common landform ESCA

esker Glacial landform ESKE

fault scarp Tectonic landform FASC

fault trace Tectonic landform FATR

flood plain Fluvial landform FLPL

fold Tectonic landform FLDS

foredune Eolian landform FORE

frost action Periglacial subprocess FRAC

glaciated uplands Landscape term GLUP

gorge Common landform GORG

graben Landscape term and tectonic landform GRAB

ground moraine Glacial landform GRMO

gully Common landform GULL

hanging valley Glacial landform HAVA

hillslope bedrock outcrop Mass wasting element landform HIBO

The landform list in the following table is based on Haskins et al. (1998).
108 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

hogback Fluvial landform HOGB

interdune flat Eolian landform INFL

interfluve Common landform INTE

intermontane basin Landscape term INBA

kame Glacial landform KAME

karst Landscape term KRST

kettle Glacial element landform KETT

kettled outwash plain Glacial landform KEOP

lahar Volcanic landform LAHA

lake Lacustrine landform LAKE

lake bed Lacustrine landform LABE

lateral moraine Glacial landform LAMO

lava flow (undifferentiated) Volcanic landform LAFL

loess deposit (undifferentiated) Eolian landform LODE

meander scar Fluvial element landform MESR

medial moraine Glacial landform MEMO

mesa Fluvial landform MESA

monocline Tectonic landform MONO

moraine (undifferentiated) Glacial landform MORA

mud flat Coastal marine landform MUFL

outwash fan Glacial landform OUFA

outwash plain Glacial landform OUPL

outwash terrace Glacial landform OUTE

oxbow Fluvial element landform OXBO

pediment Fluvial landform PEDI

permafrost Periglacial subprocess PERM

point bar Fluvial element landform POBA

pyroclastic flow Volcanic element landform PYFL

recessional moraine Glacial landform REMO

ridgetop bedrock outcrop Mass wasting element landform RIBO

rock glacier Mass wasting landform ROGL

rock slide-rock fall Mass wasting landform RSRF

rotational slide Mass wasting landform ROSL

saddle Common landform SADD

sand boil Microfeature SABO

sandhills Landscape term SAND

scarp Common landform SCAR

seep Common landform SEEP

shield volcano Volcanic landform SHVO

sinkhole (undifferentiated) Solution landform SINK

slide Mass wasting subprocess SLID

slough Common landform SLOU

slump pond Lacustrine landform SLPO

solifluction lobe Mass wasting landform SOLO

stream terrace (undifferentiated) Fluvial landform STTE

syncline Tectonic landform SYNC

talus Common landform TALU

tarn Lacustrine landform TARN

terminal moraine Glacial landform TEMO

till plain Landscape term TIPL

valley floor Fluvial element landform VAFO

Reference 

Haskins, D.M.; Correll, C.S.; Foster, R.A.; et al. 1998. A 

geomorphic classification system. Washington, DC: U.S. 

Department of Agriculture, Forest Service. 110 p.

Geomorphic term Process/landform Code
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 109

Appendix 9. Random Number Generation

Techniques to generate random numbers:

 Random number table.

§ The following table has randomly arranged numbers 

between 0 and 19.5 (which is the range needed for 

transect and quadrat intervals).

§ Close eyes and point to a spot on the table to generate a 

random number.

§ If a number outside of the appropriate range is selected, 

then repeat the process.

12.5 5 16.5 4

10.5 10 19.5 7

14 2 2.5 14.5

13.5 17.5 11.5 1

8 4.5 17 0

1.5 7.5 18.5 6.5

15.5 16 8.5 5.5

0.5 9.5 15 9

6 3.5 13 12

3 18 11 19

 Stopwatch. 

§ Start and stop a stopwatch (chronometer) and use the 

last two digits (such as hundredths of a second) as the 

random number. 

§ If a number outside of the appropriate range is selected, 

then repeat the process.
110 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 111

Appendix 10. Plant Labels (cut along dashed lines)
112 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 113

Appendix 11. Measurement of Discharge at Springs and Wetlands

1. Introduction

Measurement of discharge at springs and wetlands, although 

similar to such measurements in streams, presents additional 

challenges. Each site is unique, so that a measurement method 

that may be appropriate at one site may not be appropriate at 

another site. The field investigator must evaluate each site and 

choose the appropriate method to use, and, if necessary, modify 

the method to adjust to conditions at the site. For example, if 

discharge at a spring or wetland site is diffuse or coming from 

several points, a channel might be dug to incorporate such diffuse flow into a single channel that can then be measured.

These instructions are modified from Rantz et al. (1982). Additional information may be obtained from sources listed in the 

reference section.

2. Purpose

This is a description of techniques for measurement of discharge at springs and in wetlands that have flowing waters. The 

situations and methodologies discussed include the following: 

 Current meter.

 Timed observation of floats. 

 Volumetric measurement. 

 Use of a calibrated portable weir plate. 

 Use of a calibrated portable Parshall flume.

 Static head change procedure.

 Visual estimate.

3. Key Scientific Concepts, 

Considerations, and Assumptions

Measuring the discharge of some springs and wetlands can be 

challenging because the amount of discharge is small, waters 

are usually shallow and broadly and unevenly spread over a 

wide area, and areas with moving water are sometimes limited. 

Multiple observations are recommended to quantify precisely 

the hydrologic period or long-term discharge characteristics 

because discharge changes diurnally, seasonally, and annually.

The way the flow (or discharge) is measured will vary depending on the site-specific factors, therefore, a variety of methods 

are presented. Table 11.1 lists the various instruments recommended for a range of discharge conditions. 

Hanging gardens and limnocrenes, in particular, present a challenge for measuring flow. Flow measurements at a hanging garden could be taken at the base of the wall where flow coalesces 

into a channel. If this is not possible, photo documentation of 

the wetted area of rock face is an option. For limnocrenes that 

do not have outflow, the static head change method is used. For 

limnocrenes that have an outflow, one of the other measurement 

techniques described in the following paragraphs would be 

appropriate.

If a single channel exists, the discharge measurement should 

be taken as close as possible to the spring orifice. If multiple 

channels exist, and if they all converge to a single channel, 

the discharge can be measured in the single channel as close 

as possible to the confluence of all of the multiple channels. 

Alternatively, the flow at each orifice can be measured. 

Table 11.1.—Recommended methods to measure discharge 

based on flow (Stevens et al. 2006).

Discharge (metric) Discharge (gpm) Instrument(s)

< 10 mL/s < 0.16 Volumetric

10 to 100 mL/s 0.16 to 1.6 Weir, volumetric

0.1 to 1 L/s 1.6 to 16 Weir, flume

1 to 10 L/s 16 to 158 Weir, flume

10 to 100 L/s 158 to 1,585 Flume

0.1 to 1 m3

/s 1,585 to 15,850 Current meter

1 to 10 m3

/s 15,850 to 158,500 Current meter

> 10 m3/s > 158,500 Current meter

Note: Of all of the instruments listed, the flume is the largest and 

most difficult to carry. Therefore, it should not be carried into the back 

country unless it is essential to obtain an accurate measurement or 

if the spring has a discharge magnitude making a flume the optimal 

instrument.

3.1 Accuracy of Discharge Measurements

Accuracy of a discharge measurement is dependent on many 

factors, including the equipment used, the location and characteristic of the measuring section, the number and spacing of measurements, the rate of change in stage, the measurement depth and 

velocity, presence of ice and/or debris, wind, and (especially) 

the experience of the person conducting the measurement (Turnipseed and Sauer 2010, p. 79). The accuracy is often evaluated 

qualitatively, taking all of these factors into account.
114 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

See Rantz et al. (1982) and Turnipseed and Sauer (2010) for 

information on field equipment used for some of the methods 

described in the following section. 

4. Procedure

4.1 Current Meter

A current meter is an instrument used to measure the velocity 

of flowing water at a specific point in a channel. Several types 

of current meters are now available. Selecting which meter to 

use at a site will depend on purpose, site conditions, and cost. 

Historically, the U.S. Geological Survey (USGS) has used 

vertical-axis current meters (price current meter), which are 

mechanical devices that use spinning cups to measure the current velocity (Rantz et al. 1982, pp. 86–88). A smaller version 

(pygmy meter) is used at sites where water is shallow, such 

as a spring or wetland. Advancements in acoustic technology 

have led to important developments in the use of acoustic 

Doppler current profilers, acoustic Doppler velocimeters, and 

other emerging technologies for the measurement of discharge. 

These new instruments, based on acoustic Doppler theory, 

have the advantage of no moving parts, and in the case of the 

acoustic Doppler current profiler, quickly and easily provide 

three-dimensional stream-velocity profile data through much 

of the vertical water column. Additional information on current 

USGS stream-gaging procedures, including information on 

use of electronic field notebooks and personal digital assistants 

(PDAs), is available in Turnipseed and Sauer (2010).

Current meters are necessary in springs or in wide channels 

or high-discharge channels where flow cannot be routed into 

a weir or a flume. Measurement locations are selected in a 

straight reach where the streambed is free of large rocks, 

weeds, and protruding obstructions that create turbulence and 

where a flat streambed profile occurs to eliminate vertical 

components of velocity.

The cross-section of the channel is divided into partial sections, 

and the area and mean velocity of each section is measured 

separately. A partial section is a rectangular region in which 

depth is equal to the depth measured at that location, and for 

which width is equal to the sum of half the distances of adjacent verticals. At each vertical, the following observations are 

recorded on the data sheet: (1) the distance to a reference point 

on the bank along the tag line, (2) the depth of flow, and (3) the 

velocity as indicated by the current meter. The velocity should 

be measured at a depth that is 0.6 of the depth from the surface 

of water in the channel. The discharge of each partial section is 

calculated as the product of mean velocity times depth at each 

vertical times the sum of half the distances to adjacent verticals. 

The sum of the discharges of each partial section is the total 

discharge.

Measurements are made by wading the stream with the current 

meter along the tag line. The person wading the channel should 

stand downstream of the velocity meter. Detailed procedures 

for use of current meters is documented in Rantz et al. (1982) 

and Turnipseed and Sauer (2010).

Accuracy of current-meter measurements can be evaluated using 

methods described by Sauer and Meyer (1992). Their study 

indicated that accuracy can range from 2-percent measurement 

error under ideal measurement conditions to 20-percent measurement error under poor conditions. Under generally normal 

conditions, standard errors of measurement range from 3 to 

6 percent.

4.2 Float Method

Floats are useful for measuring discharges at springs and wetlands, where water is shallow and velocities may be too small 

to accurately use a current meter. Floats can be almost any 

distinguishable article that floats, such as wooden disks; bottles 

partly filled with water, soil, or stones; or oranges. Floating ice 

cakes or distinguishable pieces of drift may be used if they are 

present in the stream. Fluorescent dye can also be used.

Two cross-sections are selected along a reach of straight channel for a float measurement. The cross-sections should be far 

enough apart so that the time the float takes to pass from one 

cross-section to the other can be measured accurately. A travel 

time of at least 20 seconds is recommended, but a shorter time 

may be used for streams with such high velocities that it is not 

possible to find a straight reach of channel having adequate 

length. The distance between the two sections is measured with 

a measuring tape, and recorded. The width and depth of each 

channel cross-section is measured with a tape measure and recorded. In making a float measurement, the float is introduced a 

short distance upstream from the upstream cross-section so that 

it will be traveling at the speed of the current when it reaches 

the upstream section. A stopwatch is used to time its travel 

between the end cross-sections of the reach. This procedure is 

repeated 3 to 5 times, as the float is placed at different locations 

across the channel at the upstream cross-section. The average 

velocity of the measurement is then calculated. An example 

field sheet for use with this method is shown in table 11.2. 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 115

The velocity of the float is equal to the distance between the 

end cross-sections divided by the time of travel. The mean 

velocity in the vertical is equal to the float velocity multiplied 

by a coefficient whose value is dependent on the shape of the 

vertical-velocity profile of the stream and on the depth of immersion of the float with respect to stream depth. Coefficients 

of 0.85 to 0.88 are commonly used to convert the velocity of a 

surface float to mean velocity in the vertical (Turnipseed and 

Sauer 2010, p. 85). 

The procedure for computing the discharge is similar to that 

used in computing the discharge for a conventional currentmeter measurement. Discharge is computed by multiplying the 

area of the channel by the mean vertical velocity.

Float measurements of discharge that are carefully made under 

favorable conditions may be accurate to within +/- 10 percent. 

Wind may adversely affect the accuracy of the computed 

discharge due to its effect on the velocity of the floats. If a 

nonuniform reach is selected, measurement results may be in 

error by as much as 25 percent. 

4.3 Volumetric Measurement

The volumetric measurement of discharge is the most accurate 

method of measuring small flows (less than a few gallons per 

minute). The time required to fill a container of known capacity, or the time required to partly fill a calibrated container to 

a known volume, is recorded. The only equipment required, 

other than the calibrated container, is a stopwatch.

Volumetric measurements are usually made where the flow is 

concentrated in a narrow stream, or can be so concentrated, so 

that all the flow may be diverted into a container. Examples of 

sites presenting the opportunity for volumetric measurement 

of discharge are a V-notch weir, a natural or artificial control 

where all the flow is confined to a notch; or a cross-section 

of natural channel where a temporary earth dam can be built 

over a pipe of small diameter, through which the entire flow 

is directed. Sometimes it is necessary to place a trough against 

the artificial control to carry the water from the control to the 

calibrated container. If a small temporary dam is built, the 

stage behind the dam should be allowed to stabilize before the 

measurement is begun. The measurement should be made three 

or four times to be certain no errors have been made and to be 

sure the results are consistent. Several calibrated containers of 

varying sizes should be taken to the field site.

4.4 Portable Weir Plate

A portable weir plate is useful for determining discharge when 

depths are too shallow and velocities too low for a reliable 

current-meter measurement of discharge. A 90-degree V-notch 

weir is particularly suitable because of its sensitivity at low 

flows. The USGS commonly uses three different sizes of weir 

plate; their recommended dimensions are given in figure 11.1. 

The weir plate is made of galvanized sheet iron, using 10- to 

16-gauge metal. The 90-degree V-notch that is cut in the plate 

is not beveled but is left with flat, even edges. A staff gage, 

attached to the upstream side of the weir plate with its zero at 

the elevation of the bottom of the notch, is used to read the head 

on the weir. The staff gage should be installed far enough from 

the notch to be outside the region of drawdown of water going 

through the notch. Drawdown becomes negligible at a distance 

from the vertex of the notch that is equal to twice the head on 

the notch. Consequently, if the weir plate has the dimensions 

recommended in figure 11.1, the staff gage should be installed 

near one end of the plate. 

Table 11.2.—Example field sheet for use with the float method.

Float method

Reach length:

Trial Time elapsed Velocity

(reach length/time)

#1

#2

#3

Average velocity:

Average velocity x 0.85:

Figure 11.1.—Portable weir plate sizes.
116 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

To install the weir, the weir plate is pushed into the streambed. 

A pick or shovel may be necessary to remove stones or rocks 

that prevent even penetration of the plate. A carpenter’s level 

is used to ensure that the top of the plate is horizontal and that 

the face of the plate is vertical. Soil or streambed material is 

packed around the weir plate to prevent leakage under and 

around it. It ordinarily requires only one person to make the 

installation. 

A large weir plate of the dimensions shown in figure 11.1 can 

measure discharges in the range from 0.02 to 2.0 ft3

/s (0.00057 

to 0.057 m3/s) with an accuracy of +/- 3 percent, if the weir is 

not submerged. A weir is not submerged when air circulates 

freely around all sides of the nappe. The general equation for 

flow over a sharp-edged 90-degree V-notch weir is 

Q = Ch5/2

where 

Q = discharge, in cubic feet per second or cubic meters per 

second, 

h = static head above the bottom of the notch, in feet or 

meters, 

C = coefficient of discharge.

Each weir should be rated to determine C by volumetrically 

measuring the discharge corresponding to various values of 

head. In the absence of such a rating, a value of 2.47 may be 

used for C when British units are used, or 1.36 when metric 

units are used. 

When the weir is installed, it will cause a pool to form on the 

upstream side of the plate. No readings of head on the notch 

should be recorded until the pool has risen to a stable elevation. 

The head should then be read at half-minute intervals for about 

3 minutes, and the mean value of those readings should be used 

as the value for head in the equation to compute discharge. After 

the completion of the measurement, the weir plate is removed. 

An online method for calculating discharge using a V-notch 

weir is available at http://www.lmnoeng.com/Weirs/vweir.htm.

4.3 Portable Parshall Flume

A portable Parshall flume is another device for determining 

discharge when depths are too shallow and velocities too low 

for a current-meter measurement of discharge. The portable 

flume used by the USGS is a modified form of the standard 

Parshall flume having a 3-inch (0.076 meter) throat. The modification consists, primarily, of the removal of the downstream 

diverging section of the standard flume. The purpose of the 

modification is to reduce the weight of the flume and to make it 

easier to install. 

Because the portable Parshall flume has no downstream 

diverging section, it cannot be used for measuring flows when 

the submergence ratio exceeds 0.6. The submergence ratio is 

the ratio of the downstream head on the throat to the upstream 

head on the throat. Although a submergence ratio of 0.6 can 

be tolerated without affecting the rating of the portable flume, 

in practice the flume is usually installed so that the flow freely 

passes the throat, without being slowed by ponding below the 

flume. That installation is usually accomplished by building up 

the streambed a couple of inches under the level converging 

floor of the flume. Figure 11.2 shows the plan and elevation of 

the portable Parshall flume. The gage height or upstream head 

Figure 11.2.—Working drawing of modified 3-inch Parshall 

flume. 
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 117

on the throat is read in the small stilling well that is hydraulically connected to the flow by a 3/8-inch hole. The rating for the 

flume is given in table 11.3. 

When the flume is installed in the channel, the floor of the 

converging section is set in a level position by using the level 

bubble that is attached to one of the braces (fig. 11.2). A 

carpenter’s level can be used for that purpose if the flume is 

not equipped with a level bubble. Soil or streambed material 

is then packed around the flume to prevent leakage under and 

around it. After the flume is installed, water will pool upstream 

from the structure. No gage-height readings should be recorded 

until the pool has risen to a stable level. As with the portable 

weir, after stabilization of the pool level, gage-height readings 

should be taken at 30-second intervals for about 3 minutes. The 

mean value of those readings is the gage height used in table 

11.3 to obtain the discharge. A carefully made measurement 

should have an accuracy of +/- 2 or 3 percent. After completion 

of the measurement, the portable flume is removed.

4.6 The Static Head Change Procedure

This method may be used for a relative comparison value for 

change in elevation of standing pools or limnocrenes with 

no outflow. A staff gage is placed in the standing pool and 

relative gage elevation recorded, or efforts are made to locate 

and record an existing fixed point in or near the standing pool 

and the vertical distance to the pool surface recorded. Periodic 

measurements of changes in the static head on the staff gage or 

fixed point are recorded.

4.7 Visual Estimate

Site conditions, such as dense vegetation cover, steep or flat 

slope, diffuse discharge into a marshy area, and limited or dangerous access sometimes do not allow for a direct measurement 

of discharge by the techniques listed previously. Typically, the 

visual estimate method is used along with a gross estimate of 

flow velocity with a float but is only recommended as a last 

resort. Discharge class is estimated based on those listed in 

table 11.1. Photographs should be taken to record the surface 

area wetted or covered by water and observations recorded on 

a datasheet. Also, it should be noted if another method could be 

recommended to measure discharge for future site visits.

5. Documentation and Data 

Management

The name, serial number (if available), accuracy of the instrument used to measure discharge, and any other important 

observations should be recorded. Important observations may 

include the markers of any recent high discharges, such as high 

water marks, oriented vegetation, or debris on or above the 

channel or floodplain.

All computation sheets for discharge calculations should be 

neat and legible. Errors or modifications should be indicated 

by a single line drawn through them (no erasures or blackouts). 

These computations should be checked by an independent 

Gage height (ft) Discharge (ft3/s) Gage height (ft) Discharge (ft3/s) Gage height (ft) Discharge (ft3/s)

0.01 0.0008 0.21 0.097 0.41 0.280

0.02 0.0024 0.22 0.104 0.42 0.290

0.03 0.0045 0.23 0.111 0.43 0.301

0.04 0.0070 0.24 0.119 0.44 0.312

0.05 0.010 0.25 0.127 0.45 0.323

0.06 0.013 0.26 0.135 0.46 0.334

0.07 0.017 0.27 0.144 0.47 0.345

0.08 0.021 0.28 0.153 0.48 0.357

0.09 0.025 0.29 0.162 0.49 0.368

0.10 0.030 0.30 0.170 0.50 0.380

0.11 0.035 0.31 0.179 0.51 0.392

0.12 0.040 0.32 0.188 0.52 0.404

0.13 0.045 0.33 0.198 0.53 0.417

0.14 0.051 0.34 0.208 0.54 0.430

0.15 0.057 0.35 0.218 0.55 0.443

0.16 0.063 0.36 0.228 0.56 0.456

0.17 0.069 0.37 0.238 0.57 0.470

0.18 0.076 0.38 0.248 0.58 0.483

0.19 0.083 0.39 0.259 0.59 0.497

0.20 0.090 0.40 0.269

Table 11.3.—Rating table for 3-inch modified Parshall flume.
118 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

reviewer. Copies of computation sheets should be kept in 

project files and archived according to required procedures. 

Electronic copies of computations should be archived in the 

appropriate database.

6. Additional Information

American Society for Testing and Materials. 2007. Standard 

method for open-channel flow measurement of water with thinplate weirs. ASTM D5242 - 92(2007). West Conshohocken, 

PA. http://www.astm.org/Standards/D5242.htm. (21 November 

2011).

Desert Managers Group. 2001. Protocol for hydrologic data to 

be collected at desert wetland sites by BLM and NPS personnel 

in support of the California DMG water study. 4 p. http://

www.dmg.gov/documents/PRT_Springs_Data_Collection_

DMG_052401.pdf. (21 November 2011).

International Organization of Standards. 1980. Water flow 

measurement in open channels using weirs and venturi flumes—

Part 1: thin plate weirs. ISO 1438/1-1980(E). http://global.ihs.

com. (21 November 2011).

Oberg, K.A.; Morlock, S.E.; Caldwell, W.S. 2005. Qualityassurance plan for discharge measurements using acoustic 

Doppler current profilers. U.S. Geological Survey Scientific 

Investigations Report 2005-5183. 35 p. http://pubs.usgs.gov/

sir/2005/5183. (21 November 2011).

U.S. Department of the Interior, Bureau of Reclamation. 1997. 

Water measurement manual. 3rd ed. http://www.usbr.gov/pmts/

hydraulics_lab/pubs/wmm/index.htm. (21 November 2011).

7. References 

Rantz, S.E. et al. 1982. Measurement of stage and discharge. 

In: Measurement and computation of streamflow: volume 1. 

U.S. Geological Survey, water-supply paper 2175. 313 p. 

http://pubs.usgs.gov/wsp/wsp2175/. (21 November 2011).

Sauer, V.B.; Meyer, R.W. 1992. Determination of error in 

individual discharge measurements. U.S. Geological Survey 

Open-File Report 92-144. 21 p. http://water.usgs.gov/software/

MEASERR. (21 November 2011).

Stevens, L.; Kloeppel, H.; Springer, A.; Sada, D. 2006. Terrestrial springs ecosystems inventory protocols. Cooperative 

Agreement Number CA 1200-99-009, TASK# NAU-118. 

Flagstaff, AZ: National Park Service. 45 p.

Turnipseed. D.P.; Sauer, V.B. 2010. Discharge measurements 

at gaging stations. In: U.S. Geological Survey techniques and 

methods, book 3, chap. A8. 87 p. http://pubs.usgs.gov/tm/tm3-

a8/. (21 November 2011).
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 119

Appendix 12. Identification of Freshwater Invertebrates

This appendix has representative drawings of groups of aquatic 

macroinvertebrates important in springs and other groundwaterdependent ecosystems. A substantial amount of training is needed 

to identify many macroinvertebrate species, but identifying most 

groups (such as order or family) and many nonnative species 

may be accomplished with minimal training. These descriptions and illustrations can facilitate identification of important 

taxa in the field. Useful references that provide more detail 

include A Guide to Common Freshwater Invertebrates of North 

America (Voshell 2002) and Aquatic Entomology: The Fisherman’s and Ecologist’s Illustrated Guide to Insects and Their 

Relatives (McCafferty 1981). At the end of this appendix is a 

“Key to Macroinvertebrate Life in the River,” developed by the 

University of Wisconsin, in an easy-to-use flowchart format.

The following illustrations, other than those in the “Key to 

Macroinvertebrate Life in the River,” were drawn by Luke 

Boehnke.

All three insect orders described in 12.1 to 12.6 leave the water 

to mate as winged adults. Large swarms of mating mayflies and 

caddisflies often occur when all the individuals of a single species emerge at the same time. The females of all three groups 

fly upstream and drop their eggs onto the water or dive into the 

stream to attach them to rocks or leaves.

12.1 12.2

12.1–12.2. Mayflies are insects that spend most of their lives in 

streams, emerging briefly as adults to mate and lay eggs. Many 

species have gills that are visible along the abdomen. Most 

mayflies have three tails, but some have only two tails. Mayfly 

diversity declines as aquatic conditions are degraded; mayflies 

are particularly sensitive to mine waste. (Size: 6 to 25 millimeters)

12.3 12.4

12.3–12.4. Stonefly nymphs are almost always found in flowing 

water. Some stoneflies feed on other invertebrates while other 

taxa eat dead organic matter and have a preference for coarse 

substrate. Stoneflies look similar to mayflies but are stockier, 

have two claws (rather than one) on each foot, and have two 

tails instead of the usual three in mayflies. There are no gills on 

the abdomen. Diversity of these animals declines rapidly at the 

first sign of human disturbance. (Size: 12 to 40 millimeters) 

12.5 12.6

12.5–12.6. Caddisflies are insects that emerge to mate as winged 

adults. They use silk to build cases from gravel, twigs, needles, 

or sand. The larva is caterpillar-like with three pairs of legs, 

two claws at the posterior (rear) end of the abdomen, and a 

tendency to curl up slightly. They may be found in a stick, rock, 

or leaf case, with the head sticking out. Different species build 

distinct cases or chambers, often on or under rocks. Free-living 

caddisfly larvae do not build cases; many are predators and 

need to move quickly to capture other animals for food. Some 

caddisflies are very sensitive to human disturbance, but others 

are tolerant. (Size: 12 to 40 millimeters)
120 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

12.7 12.8 12.9 12.10

12.7–12.10. These four families of true bugs commonly occur in 

western North American springs. True bug larvae look similar 

to the adults. They can be distinguished from other aquatic 

insects by the following combination of characteristics: mouthparts are an elongated beak that folds back under the head when 

not feeding; wingpads are present on the thorax, three pairs of 

segmented legs have two claws on some of them, and no gills 

are present.

12.11 12.12

12.11–12.12. Riffle beetle larvae are specially adapted to cling 

to smooth rocks in fast-flowing water (riffles). After emergence, 

adults fly for a short time but return to water to feed in the same 

habitat as the larvae. Both larvae and adults are rather small 

and tend to drift to the bottom of a sample. Many beetle families 

occur in aquatic habitats, but comparatively few crenobiontic 

species exist. In the Western United States, most crenobiontic 

riffle beetles are in two genera, Stenelmis and Microcylloepus. 

Differentiating between these genera is difficult in the field 

because individuals are small (less than 3 millimeters long) and 

difficult to examine without magnification. They are easy to see 

in samples, however. Riffle beetles are black or dark brown 

with long, spindly legs. They move slowly by crawling, and 

they have weak swimming ability. (Size: less than 3 millimeters)

12.13

12.13. Long-toed water beetles are common in riffles and on 

woody debris or rocks. Adults use long, sharp claws to cling to 

debris and sometimes they crawl on the bottom or along the 

shore. The body is dull gray or brown and often covered with 

fine hairs, and the head is mostly withdrawn into the thorax. 

(Size: 4 to 8 millimeters) 

12.14

12.14. Many species of true flies exist, but in springs, there are 

three main groups or families. Midge larvae (or chironomids) 

are very small (up to 6 millimeters), often C-shaped, with a 

segmented body and a spastic squirming movement. They are 

often whitish to clear, but are occasionally bright red. Midge 

larvae have distinct heads with two small prolegs in the front 

of the body and are often attached to debris by their tiny legs. 

Blackfly larvae (or simuliids) are dumb-bell shaped and soft 

(up to 6 millimeters). The body is larger at the rear end, similar 

to the shape of a bowling pin. The distinct head contains fanlike mouth brushes. Blackfly larvae often curl into a “u” shape 

when held in your hand. They attach themselves to the stable 

substrate such as rocks, large wood, or rooted vegetation. Crane 

fly larvae (or tipulids) are large (8 to 60 millimeters) with a 

fleshy, worm-like, segmented body with finger-like projections 

(gills) at the back end. They occur in a variety of colors (clear, 

white, brown, and green) and bury themselves in soft sediment.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 121

12.15

12.15. Flatworms (e.g., Planaria), roundworms (nematodes), 

and freshwater segmented worms (oligochaetes, leeches, earthworms) are properly called worms, but should not be confused 

with the soft-bodied larvae of flies. Nematodes and oligochaetes 

are long, thin, and writhe like snakes, while planarians glide. 

These animals do not have legs.

12.16

12.16. Amphipods (or scuds) occur in many springs and are 

usually very numerous. They are comparatively large (up to 10 

millimeters long), active, and easy to identify in a macroinvertebrate sample. Amphipods are very fast swimmers that look 

like shrimp. They have many appendages that give them a 

fuzzy appearance. Amphipods can be common in very degraded sites. Isopods (or sowbugs) are usually found creeping 

through leaf litter. They have a flat, segmented body (6 to 20 

millimeters) with an “armored” appearance and seven pairs of 

legs. Unlike amphipods, isopods are flattened top to bottom.

12.17

12.17. Ostracods (seed shrimp) are the oldest known microfauna and have been extensively used in paleoclimate studies. 

They are small (usually less than 2 millimeters long), flattened 

animals with a calcitic shell and an external morphology that is 

similar to a plant seed. They are brown to pale olive green or 

gray, active, and usually easy to see in a sample because they 

constantly move. Ostracods may occur in the water column or 

on the substrate and are usually abundant in springs.

12.18

12.18. Crayfish generally occur only in large springs that do not 

dry. In some places, nonnative crayfish have been introduced 

into springs, with often dramatic negative effects on native 

plants and animals.

12.19 12.20

12.19–12.20. Springsnails are small, black or brown crenobiontic species that have an operculum (lid) and a shell that opens 

on the right. Most species in southern U.S. deserts are in the 

genera Pyrgulopsis or Tryonia, which occur in two general body 

forms. Most Pyrgulopsis species are round and slightly inflated, 

while most Tryonia species are elongated. Pyrgulopsis species 

generally occur on gravel and cobble substrates and on watercress 

in areas with higher water velocity. Tryonia species are usually 

found in slow currents where there are fine substrates. (Size: 

less than 5 millimeters) 
122 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

12.21

12.21. Physid snails are found in springs and, although some are 

introduced, many are native and likely endemic. There is no 

operculum, and the shell opens on the left. (Size: 5 to 20 millimeters)

12.22

12.22. Fingernail clams are small and usually bury themselves 

in habitats with fine sediment and low current velocity. They 

may be tan colored, but they are usually white and often translucent. Magnification is needed to differentiate species, which 

precludes field identification of species. When present, they are 

usually common and comparatively easy to find. (Size: 2 to 5 

millimeters wide)

12.23

12.23. Red-rimmed melania (Melanoides tuberculata) is a mollusk that was introduced into North America from Asia by the 

aquarium trade and has become widespread throughout the 

Western United States. It is parthenogenic (reproduces asexually) 

and can survive long periods out of water. It can be easily transplanted, is tolerant of harsh conditions, and prefers warm, slow 

water and fine substrates. Red-rimmed melania is easy to identify 

by its distinctive shape and color. It is long and conical, with 

body whorls terminating at a sharp point. Its shell is slightly 

sculptured and its coloration is an attractive and distinct mottled, 

reticulated mixture of tan and brown. Because these mollusks 

are easily transported, care should be taken to completely clean 

and inspect field gear to ensure they are not carried and introduced into other springs. (Size: up to 25 millimeters)

The following “Key to Macroinvertebrate Life in the River” 

was developed by the University of Wisconsin.
Groundwater-Dependent Ecosystems: Level II Inventory Field Guide 123
124 Groundwater-Dependent Ecosystems: Level II Inventory Field Guide

References 

McCafferty, W.P. 1981. Aquatic entomology: the fisherman’s 

and ecologist’s illustrated guide to insects and their relatives. 

Boston, MA: Science Book International. 448 p.

Voshell, J.R., 2002. A guide to common freshwater invertebrates of North America. Blacksburg, VA: McDonald and 

Woodward Publishing Co. 442 p.