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RIPARIAN AREA MANAGEMENT

Greenline

Riparian-Wetland

Monitoring

by

Jim Cagney

Range Conservationist

Bureau of Land Management

Grass Creek Resource Area, Wyoming

Technical Reference 1737-8

1993

U.S. Department of the Interior

Bureau of Land Management

Service Center

P.O. Box 25047

Denver, CO 80225-0047
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Acknowledgements

The concepts associated with the greenline monitoring method were originated by

Alma H. Winward of the Forest Service Intermountain Region. This publication

could not exist without both his ideas and his support of my attempts to apply them.

The author wishes to thank Don Prichard, Todd Christensen, and Dan Tippy for their

support during the 5-year period of trial and error which ultimately led to this publication.

The author also wishes to extend a special thanks to Linda Hill, Writer/Editor, and the

Technology Transfer Staff at the Service Center for doing a fine job in editing, layout,

design, and production of the final document.
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Table of Contents

Page

I. Introduction .....................................................................................................1

II. Purpose ............................................................................................................3

III. The Greenline ..................................................................................................5

A. The Greenline Concept ..............................................................................5

B. Greenline Definition ..................................................................................5

IV. Riparian Community Types ............................................................................7

V. Field Procedures ..............................................................................................9

A. Materials ....................................................................................................9

B. Transect Location ......................................................................................9

C. Recording Plant Community Data Along the Greenline ...........................9

D. Woody Species Counts ............................................................................14

E. Cross-Section Transects ..........................................................................15

F. Photopoints ..............................................................................................15

VI. Greenline Monitoring Method Applications .................................................17

A. Perennial Creek Study .............................................................................17

B. Intermittent Creek Study .........................................................................23

VII. Relationship and Use with BLM Planning and Implementation

Processes........................................................................................................29

VIII. Conclusion .....................................................................................................31

Literature Cited ..........................................................................................................33

Appendix A - Data Forms .........................................................................................35

Appendix B - Common/Scientific Plant Names and Symbols ..................................43
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Greenline Riparian-Wetland Monitoring

I. Introduction

Though riparian areas are not abundant in the landscape, they have great historical

significance. The provide a variety of useful products, such as water, forage, and

firewood. Additional values such as biological diversity, water storage, and sediment

trapping have more recently been attributed to riparian areas. However the ability of

a given site to provide this range of products may be dependent upon the quality of

the vegetation present. For example, a stand of coyote willow will provide building

materials for beaver, whereas a stand of Nebraska sedge will not. Yet the dense root

mass of Nebraska sedge will provide overhanging streambanks, a key fishery habitat

feature, whereas the root system of Kentucky bluegrass will not.

Modern land management plans must address these complex relationships to establish

the best balance of multiple-use activities in riparian-wetland areas. Any activities in

riparian-wetland areas will have an impact on the vegetation community—particularly grazing. Publications such as Managing Grazing of Riparian Areas in the

Intermountain Region (Clary and Webster 1989); Technical Reference 1737-4,

Grazing Management in Riparian Areas (Kinch 1989); Managing Fisheries and

Wildlife on Rangelands Grazed By Livestock (Platts 1990); and Effects of Cattle

Grazing Systems on Willow-Dominated Plant Associations in Central Oregon

(Kovalchik and Elmore 1990) all contain a dominant theme: different grazing strategies will result in predictable changes in the vegetation community. Consequently, it

is no longer valid to prescribe grazing management changes based on vague objectives such as a desire to “improve the range.”

Streamside riparian areas have different vegetation production capacities based on a

range of factors such as soils, hydraulic controls, or slope gradient. Technical Reference 1737-3, Inventory and Monitoring of Riparian Areas (Meyers 1989), contains a

comprehensive list of stream segment components affecting potential plant community. Technical Reference 1737-7, Procedures for Ecological Site Inventory (Leonard

et al. 1992), provides the basis for determining the long-term potential vegetation

community associated with a given site. The greenline monitoring method can play

an important role in evaluating whether site-specific riparian vegetation objectives are

being met.
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II. Purpose

The Bureau of Land Management’s (BLM’s) riparian area management policy of

January 22, 1987 (USDI, 1991) contains the following statement:

“Achieve riparian area improvement and maintenance objectives through the

management of existing uses wherever feasible.”

If existing conditions are not established, it will be impossible to determine if conditions are improving or being maintained. Similarly, if objectives are not established,

success cannot be measured and direction is lost. BLM establishes objectives through

its activity planning process. A well crafted Activity Plan provides clear direction

with five essential features:

1. A description of existing conditions.

2. Measurable objectives.

3. A description of management actions designed to meet the objectives.

4. A description of how progress toward meeting objectives would be monitored.

5. A determination of how and when the plan would be evaluated.

The purpose of the greenline monitoring method is to provide riparian vegetation

information suitable for use in structuring an Activity Plan as described above. The

following sequence can be achieved:

1. The greenline monitoring method generates baseline data that describe existing conditions.

2. From these established existing conditions, measurable riparian vegetation

objectives may be formulated.

3. The site-specific objectives provide the means for selecting a management

strategy.

4. Greenline studies provide the trend data portion of the monitoring plan.

5. Rereading the data in the timeframe specified in the objectives provides the

data necessary for comparative analysis in evaluating the effectiveness of the

plan.

The greenline monitoring method is intended as a tool for land managers to use in

analyzing riparian vegetation. It is considered an addition to, and not a replacement

for, all the existing techniques currently available.

It should be noted that the greenline approach does involve one important limitation.

The central data collection procedure involves a single line intercept transect. With

data from a single transect or plot, statistical analysis, such as confidence intervals,

cannot be computed. However the data generated are not intended as a statistical

sample of the population. Rather they are a description of the transect area population itself. The transect location is carefully, as opposed to randomly, selected.

Regardless, if statistical analysis is to be performed, a different data gathering procedure may need to be considered.
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Upland Riparian Upland

Green Line Green Line

Water

Line

III. The Greenline

A. The Greenline Concept

The greenline concept is designed for measuring vegetation trends on streambanks,

but can be adapted to a variety of circumstances. The method relies on identification

of riparian plant community types on a line intercept transect.

Typically, a soil moisture gradient is exhibited when moving away from the channel

in a riparian area. In a trend transect placed in a typical western floodplain, a different soil moisture could conceivably be encountered at each plot. Attempting to

average the vegetation found in these divergent plots into a single set of data can be

problematic. The greenline is a point of reference that minimizes problems associated with changing moisture gradient.

Fixed plots placed in riparian areas are vulnerable to being washed out or silted over.

A greenline transect is a variable plot method that is repeatable independent of peak

flow events.

B. The Greenline Definition

The greenline is defined as that specific area where a more or less continuous cover

of vegetation is encountered when moving away from the center of an observable

channel. Figure 1 is a schematic stream channel cross section illustrating the location

of the greenline. When monitoring a riparian area using the greenline as a point of

reference, the objective is to identify which plant communities occupy the greenline.

By the definition above, a greenline would be encountered at a single point and one

plant community identified. In Figure 1, the greenline on the right side of the

Figure 1. Stream channel cross section shows the location of the greenline.
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streambank is a herbaceous vegetation

community. On the left, the greenline is a

shrub-dominated community with a subdominant herbaceous understory. When

vegetation data are collected, the observer

follows the greenline in a line intercept

transect recording an accumulation of

these points to compile a data set.

The greenline is often, but not necessarily,

located at the water’s edge. Areas such as

unvegetated point bars are handled by

following the line of vegetation behind the

point bar. Vegetation growing in the

channel, and islands of vegetation that do

not form continuous cover, are not part of

the greenline. Figures 2 and 3 are two

examples of locations of the greenline

along stream reaches.

Figure 2. Dotted line shows the location of the

greenline, which follows the continuous

line of vegetation along Trout Creek in

southwest Wyoming.

Figure 3. Dotted line shows the location of the greenline behind a point bar in central Utah.
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IV. Riparian Community Types

One of the most dramatic differences between upland and riparian vegetation is the

capacity for change with regard to both magnitude and timeframe. Barring major

disturbance, such as fire, a sagebrush/bunchgrass upland plant community is relatively stable. A realistic objective would involve changes in plant community composition over a 30-year period. The sagebrush/bunchgrass community type could be

expected to remain constant. In a riparian area, however, a Nebraska sedge community type could change to a Kentucky bluegrass community type in a fraction of that

period. Furthermore, identification of herbaceous riparian species, one plant at a

time, can be prohibitively difficult, particularly if the area has been grazed. Consequently, the greenline riparian monitoring method is designed to detect changes in

plant community succession along the greenline rather than change in species composition.

The publication Riparian Community Type Classification of Eastern Idaho-Western

Wyoming (Youngblood, Padgett, and Winward 1985) is the prototype for classifying

and developing a knowledge of riparian plant communities. This document contains

an established list of community types that can be determined in the field using a

dichotomous key. Technical Reference 1737-5, Riparian and Wetland Classification

and Review (Gebhardt et al. 1990), provides an overview of comprehensive riparian

classifications available.

If no comprehensive community type classification is available for your area, start

developing one. Riparian community types can be identified by observing dominance

as a function of vegetation cover. Whatever species exhibits the most cover is what is

called the community type. Community types may be defined as a single dominant or

dominant/subdominant combination.

Dominant/subdominants are identified in a size class hierarchy: tree/shrub or shrub/

grass (or grasslike). Community types such as Nebraska sedge with a subdominant of

coyote willow, for example, are not identified. If Nebraska sedge has more canopy

than willow, then the site is recorded as a Nebraska sedge community type. Herbaceous community types normally do not have subdominants, although exceptions

occur. It is normal for community types to occur with several associated species as

minor components.

It is important to work from a compiled list of community types prior to running a

transect. Attempting to identify community types concurrent with running a transect

will result in inconsistent decision making in community type identification and

reduce repeatability of the data. If no local list of community types is available, the

stream reach where the transect is to be run is inspected, and a field list of community

types likely to be encountered along the transect is constructed. Field notes that

describe associated species occurring within the community types identified should

be kept, and a local list of community types observed in the planning area should be

built continuously.
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V. Field Procedures

The greenline monitoring method actually entails three data collection procedures

designed to generate a compatible data set. Greenline composition, riparian crosssection composition, and woody species density are the data products. Based on the

site-specific circumstances, it is not always necessary to collect all the data options

described. For this reason the text is structured to provide a general overview of the

concepts and procedure, followed by two case studies in which the concept was

applied in two distinctly different ways. The example applications provide guidelines

regarding installation of transects and data analysis.

A. Materials

1. Three forms entitled Greenline Transect Data, Greenline Supplemental Data,

and Cross-Section Composition (see Appendix A).

2. Camera with film.

3. Six fence posts with post pounder or sledgehammer.

4. Compass.

5. Six readily visible markers; engineering pin flags work well.

6. Calculator.

7. One 6-foot rod.

Note: See the Perennial Creek Study section for a detailed description of how each

of these materials are used.

B. Transect Location

The data will be most useful if a transect is located entirely within a reach of comparable potential. Within a reach, a key area location without obvious changes in

factors such as slope or soils should be selected.

The greenline monitoring method is particularly useful for observing succession and

trends on sites that are relatively stable. This method has the least utility in stream

reaches that are rapidly changing through factors such as channel headcutting or

beaver activity.

C. Recording Plant Community Data Along the Greenline

The greenline is traversed over the length of an established transect and the number of

feet of each community type observed recorded on the Greenline Transect Data form

found in Appendix A. A running tally of each community type observed is recorded,

making no effort to keep track of the sequence in which the community types were

observed. For example, along the greenline there may be 5 feet of a Nebraska sedge

community type followed by 6 feet of coyote willow/Nebraska sedge, which in turn

are followed by 8 feet of Nebraska sedge. This would be recorded as:

Nebraska sedge 5 13 ft.

Coyote willow/Nebraska sedge 6 ft.
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Recording Nebraska sedge as “5, 8” with the intention to sum the total at the end is

risky practice because “5, 8” can too easily become “58” when the data are analyzed.

1. Greenline Ground Rules

The following ground rules aid in collecting valid, repeatable data:

• Transects should be a minimum of 726 feet along the greenline; this distance

provides an easy conversion to acreage. This length, 6 feet wide, computes to

1/10th of an acre.

• The width of the community type is not a factor when traversing a line intercept along the greenline. The objective is to identify the first community type

that can be observed moving away from the center of the channel. Many

factors, such as slope gradient, will determine how far this community type

extends away from the channel. If the width of a community type is considered important, a line intercept cross section is run through the riparian area as

a separate database as described in the Cross-Section Transects section.

• One foot is the minimum length along the transect a community type may

occupy to be recorded in the database. Community types shorter than this

should be combined with an adjacent community type. A 726-foot transect

could be considered as 726 1-foot plots where vegetation dominance is observed.

• The vertical downward projection from the canopy determines the vegetation

identified along the greenline. For example, a large cottonwood tree may

dominate a site even though it is not actually rooted immediately in the

greenline area.

• Community types identified do not have to be riparian vegetation; upland

community types can in many cases be the vegetation occupying the greenline

under the definition.

• Site-specific ground rules such as “only perennial vegetation was considered

in identifying the location of the greenline” may be incorporated if documented.

• Since this method relies on the ability to step off distance accurately, it is

recommended that a reliable stride be calibrated along a tape.

• Repeatability is significantly enhanced when data are reread at the same

phenological stage as when the original data were collected.

2. Greenline Troubleshooting

• In some instances, a choice may have to be made between two lines of vegetation that appear to meet the greenline definition. When a site is recovering
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Figure 4. Arrows depict upper and lower continuous lines of vegetation along Little

Spearfish Creek in western South Dakota.

Since both lines are equally continuous,

the lower line forms the greenline.

Figure 5. Arrows depict upper and lower continuous lines of vegetation along Canyon

Creek in southwest Wyoming. Since the

upper line is more continuous, the

observer has correctly chosen the upper

line as the correct greenline.

from a recent channel incision or period of heavy trampling, a new line of

vegetation often begins to form at the water’s edge below an old, established

greenline. This can occur on a very short-term basis, such as prior to the

turnout of livestock in a pasture. This common situation is illustrated in

Figures 4 and 5. Consequently, a determination of which line to observe will

have a pronounced effect on the database. In Figure 4, a pure stand of sedges

comprises the lower line, and the upper line is a mixture of sedges, shallowrooted grasses, and forbs. When this situation occurs, data are collected on

the line that appears to be most continuous; if they appear to be about the

same, the lower line is used. Figures 6 and 7 illustrate rapid movement of the

greenline over a 7-year period. The data collection procedure is designed to

accommodate the rapid change in stream channel morphology evident in the

photographs.

• A community type titled “trample” or “barren” can be used to skip over gaps

in the greenline caused by trails, etc. However, vegetation that appears

trampled should be recorded whenever possible because the site will likely

appear as a vegetation community type if observed during even a brief rest or

deferment from grazing.
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• Cut banks opposite point bars (Figure 8) and areas with slumping soils

(Figure 9) present problems in identification of the greenline when

unvegetated soil goes to the edge of the channel. The arrows in Figures 8 and

9 illustrate natural breaks that are commonly encountered in the greenline.

When this occurs, the first option is to reconsider the site as a suitable key

area. In many cases this problem can be avoided by good transect location.

The second option is to follow the continuous line of vegetation behind the

slump or cut, in which case the community type will normally be upland

Figure 6. Dotted line shows the location of the greenline along Cottonwood Creek in northwest

Wyoming, August 1982.

Figure 7. Dotted line shows the new location of the greenline along the same stream segment seen in

Figure 6, August 1989, after vegetation growth has narrowed the channel width.
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vegetation. However, this could result in too much irrelevant upland data.

The third option is to follow the water’s edge, where a greenline may be

anticipated to form, until a normal greenline situation is reencountered.

• A “rock” or “log jam” may also be cited to skip over an unvegetated area if

traversing the greenline vegetation in strict accordance with the definition

would result in lower quality data.

Figure 8. Arrow indicates where the greenline ends abruptly at a cutbank opposite a point bar along

Red Canyon Creek in northwest Wyoming.

Figure 9. Arrows show where slumping soils create breaks in the greenline along Vermillion Creek in

southwest Wyoming.
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• When special situations such as those noted above are encountered, a narrative

of how the site was handled should be provided.

D. Woody Species Counts

Density of woody species is an ideal complement to greenline data. The transect is

retraced while holding a 6-foot rod centered over the inside edge of the greenline.

Woody species of specific concern, which are rooted in the plot formed by the 6-foot

rod are counted. These data are being collected in Figure 5. Appendix A contains a

Greenline Supplemental Data form, which is used to quantify woody species in the

transect area. The form allows for the vegetation to be tallied by either age or height

classes.

1. Multistemmed Species

Multistemmed species such as coyote willow or water birch are best tabulated in

the following age categories:

a. Seedling - This year’s growth only. Multistemmed plants such as willows

exhibit only a single stem at this growth stage.

b. Young - Immature plants that appear to show more than a single season’s

growth. Multistemmed plants exhibit 2 to 10 stems at this stage.

c. Mature <50% Dead - Vigorous healthy plants. Multistemmed plants exhibit

more than 10 stems.

d. Mature >50% Dead/Clubbed - Old declining plants; includes “mushroom”

shaped willows and any plants that exhibit a clubbed appearance from longterm heavy browsing.

2. Single-Stemmed Species

Single-stemmed species such as cottonwood are best tabulated in height classes:

0 to 3 feet, >3 to 6 feet, >6 to 10 feet, and over 10 feet. It is common to encounter

trees in atypical form as a result of flood events, etc. These trees are tallied at the

height they occur on the day observed. For example, if a 30-foot tree has been

knocked down but remains alive, the tallest part on the day observed may be the

5-foot height of a lower branch.

3. Woody Species Ground Rules

The following ground rules and tips aid in collecting valid, repeatable data:

• The rod is centered on the greenline in order to detect reproduction on point

bars between the greenline and the water’s edge. Generally, where no point

bars are encountered, half of the rod hangs out over the stream channel. When
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observing narrow streams, only those plants associated with the bank being

traversed are recorded in order to avoid counting plants twice.

• On some transects, seedlings or young plants may be too numerous to readily

count. It is sufficient to note this in lieu of a tally count.

• Identification of individual plants can be difficult, as some judgement is

required to differentiate between an individual plant and a sprout or stem. If it

cannot be reasonably assumed that two stems share a common root without

excavating soil, the two should be tallied as individuals.

• Dead plants are ignored on woody counts.

E. Cross-Section Transects

Appendix A contains a Cross-Section Composition form used to record the plant

community composition of a riparian area in general. To collect these data, a line

intercept transect is run perpendicular to the riparian area, and data are recorded in the

same manner as described in the Recording Data Along the Greenline section. The

data form is designed to record three cross-section transects. In some areas, up to five

cross-section transects may be desirable. In such cases, a second form can be used.

See the Perennial Creek Study section for more information regarding cross-section

transects.

F. Photopoints

Photopoints provide an excellent record in both interpreting the data and aiding in

repeatability. Pictures are taken to show both the transect location and the data

collected. The Greenline Supplemental Data form (Appendix A) contains a place to

record the content of photos taken.
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VI. Greenline Monitoring Method Applications

The greenline monitoring method can be adapted to observe riparian vegetation in a

variety of circumstances. Following are examples of two diverse applications.

A. Perennial Creek Study

A goal was established to improve trout habitat by increasing vegetation that shades

the creek and is capable of supporting overhanging streambanks. Data are required to

develop measurable objectives associated with this goal. Because Perennial Creek

contains important resource values and is of high public interest, all the types of data

associated with the greenline riparian monitoring method were collected.

Figure 10 is a drawing of how the greenline and three cross-section transects were

established on Perennial Creek. This was accomplished through the following steps:

Step 1 - A witness post was located in upland vegetation at the edge of the riparian vegetation zone adjacent to where the greenline transect will be initiated.

Step 2 - A second post was located in upland vegetation across the riparian zone

in a location where a line between the two posts would be perpendicular to the

riparian zone, not the creek. A pin flag was left on the greenline where it intersects this line between these two witness posts as seen on Figure 10. These two

posts and the pin flag formed the first cross-section transect and the starting point

of the greenline transect. The compass bearing or azimuth of the cross-section

transect was recorded.

Note: Witness posts were located in upland vegetation to prevent them from being

washed out, and to allow for a potential increase in the width of the riparian zone

itself.

Step 3 - The greenline was traversed upstream from the initial pin flag, placing

pin flags at 100, 200, 300, and 363 feet. The stream was crossed and the

greenline traversed back down the opposite bank 363 feet. A final pin flag was

placed there to mark the end of the greenline transect. These markers help the

observer keep track of location within the transect and provide valuable reference

points for photographs.

Note: The final pin flag is not expected to be directly opposite the starting pin

flag.

Step 4 - The second cross-section transect was installed by locating witness posts

in the same manner as in step 2, with the flag at 200 feet at the point of intersection along the greenline. In order to be perpendicular to the riparian zone, this

cross-section transect crosses the stream three times (see Figure 10).
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RIPARIAN EDGE

END OF GREEN LINE

TRANSECT PIN FLAG

(726 FT) STREAM FLOW

DIRECTION

GREEN LINE TRANSECT

STARTING POINTFIRST PIN FLAG

WITNESS POST &

CROSS SECTION

TRANSECT #1

WITNESS POST &

CROSS SECTION

TRANSECT #2

WITNESS POST &

CROSS SECTION

TRANSECT #3

100 FT PIN FLAG

200 FT PIN FLAG

300 FT

PIN FLAG

363 FT

PIN FLAG

Key Area Transects Layout

3

3

2

2

1

1

x

x

x x

x x

Step 5 - The third cross-section transect was installed with the pin flag at 363 feet

as the point of intersection along the greenline.

Note: If the stream channel moves between the time the transects are installed

and reread at a later date, the cross sections will no longer intersect the greenline

at the points 200 and 363 feet along the greenline. However the greenline transect

is always initiated at the point of intersection between the first cross-section

witness posts.

Following installation of the witness posts and marker flags, the greenline and crosssection transects were traversed according to the general instructions. Figures 11 and

12 illustrate data collection on the field forms. Appendix B contains a cross-reference

of all plant names and symbols used in this document.

Note: While traversing the transect, a calculator is helpful because the data do not

provide a running total of the distance along the transect traveled without adding the

sum of all the plant community types observed. It is valuable to stop and sum the

total communities observed at each marker, in order to keep tabs on the consistency

of your stride. At the end of the transect, the sum of all community types observed

came out to 730 feet, which is close enough to the 726 feet traversed when the markers were left. A difference greater that 5 percent is considered excessive.

Woody species were counted in age classes because the vegetation on the key area is

comprised of multistemmed willows and birches. Figure 13 is an example of data

form tabulation.

Figure 10. Key area transects layout for the Perennial Creek Study.
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GREENLINE TRANSECT DATA

RESOURCE AREA OBSERVER DATE

KEY AREA NAME ALLOTMENT # LOCATION

PLANT COMMUNITY # FEET OBSERVED PERCENT

Green River Jim Cagney 7-31-91

Perennial Creek 4007 T. 12 N., R. 106 W., Sec. 7

NWNW

CANE 5 13 20 27 32 60 78 83 101 132 144 154 21

SAEX/CANE 6 31 47 06

SAEX 10 16 37 51 07

AGST 3 19 24 31 37 40 05

ELPA 3 12 16 25 31 44 06

Trample 9 16 22 31 34 05

DECA 4 7 01

Mesic Forbs 2 6 11 02

EQAR 6 8 13 18 21 27 04

BEOC 18 23 03

ARCA 3 8 12 14 21 03

ARTR/AGDA 18 22 30 35 44 51 62 71 10

JUBA 6 15 19 37 45 52 70 78 90 12

BEOC/CANE 12 18 30 31 04

POPR 08 15 27 29 34 41 46 06

ARCA/JUBA 6 8 10 20 25 28 33 05

TOTALS 730 100

Figure 11. Example of greenline data collection.
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CROSS-SECTION COMPOSITION

RESOURCE AREA OBSERVER DATE

KEY AREA NAME ALLOTMENT # LOCATION

PLANT COMMUNITY and # FEET OBSERVED

TRANSECT #1 BEARING TOTAL RIPARIAN WIDTH

TRANSECT #2 BEARING TOTAL RIPARIAN WIDTH

TRANSECT #3 BEARING TOTAL RIPARIAN WIDTH

Green River Jim Cagney 7-31-91

Perennial Creek 4007 T. 12 N., R. 106 W., Sec.

7

NWNW

85° W 105'

ARTR/JUBA 8 12

POPR 12 23 28 38

SAEX 6 8 9 12

Creek 2

JUBA 14 22 27

CANE 7 12 14

10° N 180'

ARTR/JUBA 7 18 21 22 DECA 5 7

POPR 12 31 40 SAEX 6 16 24

JUBA 7 12 18 28 AGST 25

SAEX/CANE 6 9 12

ANRO 6 15

Creek 2 5 7

5° N 85'

ARTR 4 DECA 12 15 20

CANE 3 SAEX 8 16

Creek 4

SAEX/CANE 7 9 14

POPR 9 16 24

Figure 12. Example of cross-section data collection.
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Green River Jim Cagney 7-31-91

Perennial Creek 4007 T. 12 N., R. 106 W., Sec. 7

NWNW

SAEX numerous 22 2 3

BEOC 14 6 2

Transect located on Perennial Creek, 1.7 miles east of Uncle Billy’s Cabin on county

road #17.

- Utilization of CANE is about 35%; cattle currently using the area.

Photos:

1) First cross section witness post. 2) Start marker in foreground, 100' marker in

background. 3) 300' marker foreground, 363' marker background. 4) 363' marker in

foreground looking upstream beyond the transect area. 5) 2nd cross section.

6) 3rd cross section.

GREENLINE SUPPLEMENTAL DATA

RESOURCE AREA OBSERVER DATE

KEY AREA NAME ALLOTMENT # LOCATION

WOODY SPECIES COUNTS

AGE CLASS OPTION

SPECIES SEEDLING YOUNG MATURE MATURE

<50% DEAD >50% DEAD

HEIGHT CLASS OPTION

SPECIES 0-3' >3-6' >6-10' >10'

PHOTOS TAKEN/REMARKS:

.

. ..

 .

.

.

..

.. . ..

Figure 13. Example of multistemmed woody species data collection.
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Greenline data may be analyzed as shown in Table 1. In this example, plant communities were identified as “preferred,” “undesirable,” or “other” according to their

value for watershed stability, ability to shade the creek, ability to form overhanging

banks, and forage.

Table 1. Data Analysis—Perennial Application

Description of the Perennial Creek Key Area

Preferred Undesirable Other

Community Types Community Types Community Types

(Percent) (Percent) (Percent)*

Plant communities observed in the greenline transect:

SAEX 07 ARCA 03 ARCA/JUBA 05

CANE 21 ARTR/AGDA 10 ELPA 06

BEOC 03 TRAMPLE 05 EQAR 04

JUBA 12 POPR 06 AGST 05

DECA 01 MESIC FORBS 02

BEOC/CANE 04

SAEX/CANE 06

TOTAL 54 26 20

Plant communities observed (in aggregate) in the cross-section transects:

DECA 07 POPR 28 ARTR/JUBA 09

CANE 11 ANRO 04 AGST 07

SAEX 07 ARTR 01

SAEX/CANE 07 CREEK 02

JUBA 15

TOTAL 47 33 18

* Other community types include features that are neither preferred nor undesirable,

such as some creek crossings, rock outcrops, and some vegetation communities.

Communities having similar values were grouped together to establish the desired

plant community objectives shown on Table 2. Desired plant community objectives

were based on the specific site capability and formulated by an interdisciplinary team.

Additional objectives were developed from the other data collected, involving the

amount and age structure of key woody riparian species, and the width and composition of the riparian area itself.

Note: The occurrence of additional willow and sedge species would be considered

advantageous; however, only species currently present were cited in the 5-year term

desired plant community objectives. Use of short-term objectives is recommended

when the long-term potential cannot be determined with an acceptable degree of

confidence. However, it should be clearly stated that the short-term objectives are

considered an incremental step to be updated at the scheduled evaluation.
29

Table 2. Riparian Community Type Objectives

Greenline Plant

Community Types (CTs) 1992 Desired Plant Community 1997

SAEX-BEOC DOMINANT CTs 20% INCREASE TO 30%

CANE 21% INCREASE TO 30%

JUBA 12% MAINTAIN AT 15%

POPR, FORB, ARTR, & ARCA CTs 26% DECREASE TO 10%

OTHER 21% DECREASE TO 15%

By 1997:

• Increase the dominance of preferred community types in the cross-section

transects by 10 percent, with a corresponding decrease in undesirable community

types.

• Maintain or increase existing average riparian width of 123 feet.

• Allow at least 10 of the young or seedling willow and birch plants to reach the

mature stage and maintain the existing age structure, given all size classes represented, with the younger classes most numerous.

B. Intermittent Creek Study

The Intermittent Creek Drainage is an important source of sedimentation in a major

river system. A goal was established to increase those plant communities that promote channel stability. Site-specific data were needed to evaluate grazing management in an allotment containing 2 miles of the creek.

In this 2-mile reach, flow volume and duration are greater in the upper reaches,

declining steadily lower in the drainage. While a greenline is apparent in the upper

reaches, intermittent, unreliable flow in the lower reaches produces areas of spotty

riparian vegetation establishment, particularly on point bars, where no greenline can

readily be observed. Because this stream produced riparian vegetation in sporadic

patches, a determination was made that the cross-section transects would not provide

meaningful information; consequently, they were omitted from the study.

The stream was divided into three key area reaches of similar site potential as a

function of water availability. These reaches of similar potential are of unequal

length as shown on Figure 14. Materials needed included the Greenline Transect

Data and Greenline Supplemental Data forms and a camera with film.
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Figure 14. Transect layout—Intermittent Creek study.

A preliminary evaluation revealed four preferred riparian community types, including

Nebraska sedge, baltic rush, coyote willow, and narrowleaf cottonwood. A greenline

transect was traversed along both banks of the creek. When preferred riparian communities were encountered, their lengths were recorded according to the general

instructions. When other community types excluded from this list (such as rabbitbrush, Canada wildrye, and wheatgrasses) were encountered along the greenline, or

no greenline was apparent, no data were recorded until another reach exhibiting a

preferred community type was encountered. Collection of this information continued

for the entire length of Intermittent Creek in the allotment. In essence, an inventory

of the entire riparian resource was conducted, except to save time, only selected

community types were observed. The field data sheets were generated in the same

manner shown in the Perennial Creek application, and the organized results are

shown in Table 3.

Table 3. Intermittent Creek Riparian Community Type Data (1992)

Number Feet Observed

Upper II Lower

Riparian Community Type Reach Reach Reach Total

Coyote willow 295 670 379 1,344

Nebraska sedge 191 477 272 940

Narrowleaf cottonwood 36 168 102 306

Baltic rush 90 323 165 578

Aggregate Total 612 1,638 918 3,168

Boundary - Intermittent Creek Allotment

Middle Key Area

Upper Key Area

Lower Key Area

Intermittent Creek 1 Mile
31

Cottonwood trees were counted in the four height classes shown in Table 4. The data

display the number of individuals in each height class. The entire riparian area was

observed, in all three key area reaches. Consequently Table 4 displays all the individual trees known to exist in the entire allotment.

Table 4. Intermittent Creek Tree Species Data (1992)

Cottonwood Height Class Distribution (Feet)

Key Area

Reach 0-3 >3-6 >6-10 >10 Total

Upper 03 07 02 02 14

II 07 36 14 05 62

Lower 18 38 13 03 72

Total 28 (19%) 81 (55%) 29 (19%) 10 (7%) 148 (100%)

Fifteen mapped, readily identifiable photopoints were established in support of the

vegetation data.

As noted, the key area reaches derived by streamflow duration were not equal in

length. Table 5 shows the percentage of all four preferred riparian plant communities

considered in aggregate, relative to the total length of the reach. Table 5 demonstrates that the four preferred community types decline in abundance in the lower

reaches.

Note: The linear length shown on Table 5 was computed by measuring the length of

each reach on the 1:24,000 topography map scale. The vegetation data were collected

by traversing the greenline along the creek incorporating each meander at its actual

length. The percentages shown on Table 5 are an index of abundance because they

compare actual field-scale vegetation data to map-scale linear length of reach data.

Table 5. Percentage of Preferred Riparian Community Types (CTs) for Each Key Area Reach

Aggregate

Key Area Length, All Linear Length Preferred CT

Reach Preferred CTs of Reach Percentage

Upper 612 1,200 51

Middle 1,638 4,200 39

Lower 918 5,100 18

Totals 3,168 10,500
32

Table 6 depicts the number of cottonwoods in each key area reach adjusted to address

divergent reach length. The length of each reach was divided by the total number of

trees observed to yield the number of feet per tree (feet/tree), a relative measure of

tree species density. The lower the feet/tree observed, the greater the abundance of

cottonwoods. Table 6 shows that the cottonwood numbers did not appear to decline

in the lower reaches in conjunction with reliability of surface water, as do the community types shown in Table 5. This is considered an important determination in

assessing site potential.

Table 6. Abundance of Cottonwoods by Reach

Total Number Number of

Key Area Linear Length of Trees Feet/Tree

Reach of Reach Observed Observed

Upper 1,200 14 86

Middle 4,200 62 68

Lower 5,100 72 71

Tables 4 and 6 indicate that while ample tree species regeneration exists, the trees

were concentrated in the lower height classes and were not “releasing” into height

classes above 6 feet. Table 7 shows an analysis of the height class distribution for

each of the three key area reaches, when the trees are classified as either greater than

or less than 6 feet tall.

Table 7. Riparian Tree Species Height Class Distribution

Number Number

Key Area Total Number up to Greater Than

Reach Riparian Trees 6 Feet 6 Feet

Upper 14 10 4

Middle 62 43 19

Lower 72 56 16

Totals 148 109 39

Given these data and subsequent analysis, the following objectives were established

for Intermittent Creek over a 5-year period (1997):

1. Increase the preferred community type percentages depicted on Table 5 for

each reach by a minimum of 5 percent. This objective will have to be considered in conjunction with streamflow volume data, as noted in the discussion

associated with Table 5.

2. Maintain or increase cottonwood numbers. It is expected that these cottonwood objectives can be achieved independently of streamflow volume.
33

3. Allow sufficient release of tree species such that a minimum of 10 percent

(approximately 10 trees) of those individuals currently less than 6 feet tall

release into the height classes over 6 feet. About half that total should occur

in the lower key area reach.
34
35

VII. Relationship and Use with BLM Planning and

Implementation Processes

BLM will “prescribe management for riparian values that is based upon site-specific

characteristics and settings” (USDI, 1991). While Resource Management Plans may

contain general objectives or goal statements of broad intent, Activity Plans require

site-specific measurable objectives designed to be achieved within established

timeframes. The greenline monitoring method provides the means for establishing

baseline data from which site-specific objectives can be determined. Desired plant

community objectives can be developed in accordance with BLM Manual H-1734-1,

Vegetation Management Handbook.
36
37

VIII. Conclusion

Riparian objectives must be developed through an interdisciplinary approach. Prior

to establishing transects, the overall goals must be established by an interdisciplinary

team in order to determine where and what type of studies will be required. Once this

information has been derived, the greenline monitoring method is a viable alternative

for developing the vegetation portion of an Activity Plan. Greenline vegetation data

are an ideal complement to data collected by wildlife and fishery biologists, soil

scientists, and hydrologists, in order to evaluate the complex relationships found in

riparian areas.
38
39

Literature Cited

Clary, W.P. and B.F. Webster. 1989. Managing grazing of riparian areas in the

Intermountain Region. Gen. Tech. Rep. INT-263. Ogden, UT:U.S. Department of

Agriculture, Forest Service, Intermountain Research Station. 11pp.

Gebhardt, K., S. Leonard, G. Staidl, and D. Prichard. 1990. Riparian area

management: Riparian and wetland classification and review. USDI, BLM/YA/

PT-91/002+1737, Denver, CO. 56pp.

Kinch, G. 1989. Riparian area management: Grazing management in riparian areas.

USDI, BLM/YA/PT-89/021+1737, Denver, CO. 48pp.

Kovalchik, B.L., and W. Elmore. 1991. Effects of cattle grazing systems on willowdominated plant associations in central Oregon. In Ecology and Management of

Riparian Shrub Communities Symposium Proceedings. Sun Valley, ID, pp. 111-

119.

Leonard, S., G. Staidl, J. Fogg, K. Gebhardt, W. Hagenbuck, and D. Prichard. 1992.

Riparian area management: Procedures for ecological site inventory. USDI, BLM/

SC/PT-92/004+1737, Denver CO. 137pp.

Meyers, L.H. 1989. Riparian area management: Inventory and monitoring of riparian

areas. USDI, BLM/YA/PT-87/022+1737, Denver, CO. 89pp.

Platts, W.S. 1990. Managing fisheries and wildlife on rangelands grazed by livestock.

Nevada Department of Wildlife. 96pp.

USDI. 1991. Riparian-wetland initiative for the 1990’s. BLM/WO/GI-91/001+4340,

Denver, CO. 50pp.

Youngblood, A.P., W.G. Padgett, and A.H Winward. 1985. Riparian community type

classification of eastern Idaho-western Wyoming. USDA, FS/R4-ECOL-85-01,

Salt Lake City, UT. 78pp.
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41

Appendix A

Data Forms
42
43

GREENLINE TRANSECT DATA

RESOURCE AREA OBSERVER DATE

KEY AREA NAME ALLOTMENT #

LOCATION

PLANT COMMUNITY # FEET OBSERVED PERCENT
44
45

CROSS-SECTION COMPOSITION

RESOURCE AREA OBSERVER DATE

KEY AREA NAME ALLOTMENT #

LOCATION

PLANT COMMUNITY and # FEET OBSERVED

TRANSECT #1 BEARING: TOTAL RIPARIAN WIDTH

TRANSECT #2 BEARING TOTAL RIPARIAN WIDTH

TRANSECT #3 BEARING TOTAL RIPARIAN WIDTH
46
47

GREENLINE SUPPLEMENTAL DATA

RESOURCE AREA OBSERVER DATE

KEY AREA NAME ALLOTMENT #

LOCATION

WOODY SPECIES COUNTS

AGE CLASS OPTION

SPECIES SEEDLING YOUNG MATURE MATURE

<50% DEAD >50% DEAD

HEIGHT CLASS OPTION

SPECIES 0-3' >3-6' >6-10' >10'

PHOTOS TAKEN/REMARKS:
48
49

Appendix B

Common/Scientific Plant Names

and Symbols
50
51

Symbol Common Name Scientific Name

AGDA thickspike wheatgrass Agropyron dasystachyum

ANRO rose pussytoes Antennaria rosa

AGST red top Agrostis stolonifera

ARCA silver sage Artemisia cana

ARTR big sagebrush Artemisia tridentata

BEOC water birch Betula occidentalis

CANE Nebraska sedge Carex nebraskensis

CHVI green rabbitbrush Chrysothamnus viscidiflorus

DECA tufted hairgrass Deschampsia caespitosa

ELPA creeping spikesedge Eleocharis palustris

EQAR horsetail Equisetum arvense

JUBA baltic rush Juncus balticus

POPR Kentucky bluegrass Poa pratensis

POAN narrowleaf cottonwood Populus angustifolia

SAEX coyote willow Salix exigua