***[MINERAL SOIL FLATS]{.underline}* -- Wetland Functional Assessment
Model FORESTED WETLAND INDIANA July 2006**

  -------------- --------- ------- --------- ---------- -------------- --------- ---------- ----------
  **Name**                                              **County**               **Date**        

  **Performed                                                                               
  By**                                                                                      

  **Conversion                                          **Mitigation                        
  Site**                                                Site**                              

  **Farm No.**   **Tract           **Field   **Note**   **Farm No.**   **Tract   **Field    **Note**
                 No.**             No.**                               No.**     No.**      

                                                                                                 

                                                                                                 

                                                                                                 
  -------------- --------- ------- --------- ---------- -------------- --------- ---------- ----------

**Subclass Description**

This subclass of wetlands is found on a variety of landforms including
postglacial lake plains, till plains, outwash plains, and terraces.
These wetlands predominate in MLRA 99 and are common in MLRA 111, 113,
and 114. They are also scattered in other MLRAs. They are typically
distinguished by very low topographic gradients and poorly drained and
very poorly drained loamy to clayey textured soils.

The primary water source is precipitation; some sites have minor
overland runoff or groundwater inflow. They typically have seasonally
high water tables from early winter to early summer. Water tables will
fluctuate and are influenced by evapotranspiration and periodic
rainfall. Surface ponding may be extensive or may be limited just to
micro-depressions within the flat area. Ponded water typically does not
run off laterally. The primary direction of water movement is vertical
in the upper part of the soil profile, but water movement is horizontal
in soils which have slowly permeable subsoil layers.

This model is based on forested systems; this is the predominate
vegetation on these wetlands. In some of the mineral flats the original
vegetation may have been herbaceous vegetation. This model can be used
where a site has reverted to trees, but is not intended to be used on
wetland subclasses where native herbaceous plants predominate.

**Distinguishing Characteristics**

This subclass differs from organic soil flats in the region in that most
of the organic wetlands had a predominance of non-woody vegetation
before settlement, and consist of primarily organic soils, and vary in
soil biochemical conditions. The lack of significant surface inflow
distinguishes them from depressional wetlands. The reliance upon
precipitation as opposed to groundwater, and the low topographic
gradient, distinguishes flats from slope wetlands. As opposed to reverie
wetlands, the flats are primarily dependent upon precipitation with the
primary surface water movement being vertical fluctuation as opposed to
unidirectional horizontal flow. In some cases, wetlands in these other
classes may appear similar to flats and may even function similarly. For
example, direct precipitation may be equal to surface runoff as a
primary water source for very large depress ional wetlands.

**Important Functions**

Due to their flat gradient and fluctuating water tables, the primary
hydrologic function of mineral flats is to store subsurface water.
Surface water storage is a minor component and depends upon the amount
of surface ponding. The fluctuating water tables are conducive to rapid
biogeochemical nutrient cycling. Large amounts of organic carbon may be
stored in the woody biomass present in mature ecosystems of this type.
These wetlands originally occurred as a portion of extensive woodlands
which provided important habitat for a variety of plant and animal
species. Pools within the woods serve as important amphibian breeding
sites; several migratory birds use these as nesting areas.

**Current Conditions**

Mineral soil flat wetlands originally existed as a portion of extensive
forests in many areas. Due to the difficulty in clearing and draining
them, they were often the last areas settled. Currently these wetlands
exist as scattered woodlots in agricultural areas. In Indiana the
majority of these woodlots range from a few acres to approximately 50
acres. Large contiguous tract are very rare. Although many have no
artificial drainage installed (or, if installed, are not functioning)
within the wetland, extensive drainage in the surrounding landscape has
probably altered the original hydrologic regimes within the wetlands of
this subclass.

**MODEL FUNCTIONS**

**1. F~HYDRO~ -** Maintenance **of Characteristic Hydrologic Regime**

**Definition:** Capacity of a wetland to temporarily store (detain)
surface water for long durations, and store water beneath the wetland
surface. Function is associated with standing water not moving over the
surface. Subsurface storage capacity becomes available as periodic
drawdown of water table or reduction in soil saturation occurs. Sources
of water are direct precipitation, and to a lesser extent, overland
flow.

**Effects On-site:** Stores water for short- and long- term periods;
replenishes soil moisture; detains water for chemical transformations;
influences biogeochemical processes in the soil; maintains
seasonally-ponded habitat for herptiles and aquatic invertebrates;
maintains vegetative composition; retains water for establishment and
maintenance of biotic communities and influences soil characteristics.

**Effects Off-site:** Improves water quality; provides soil moisture
recharge; maintains base and seasonal flow distribution.

**F~HYDRO~ = \[( V~DRAIN~ )2 + V~DURATION~ + V~%\_PONDED~ + V~SOIL_Q~
)\] /5**

**2. F~CYCLING~** **- Nutrient Cycling**

**Definition:** Abiotic and biotic processes that convert nutrients and
other elements from one form to another; primarily recycling processes.

**Effects On-site:** removes sediments, nutrients, and contaminants; Net
effects of recycling are elemental balances between gains through import
processes and losses through hydraulic export, efflux to the atmosphere,
and long-term retention in persistent biomass and sediments.

**Effects Off-site:** To the extent that nutrients are held on-site by
recycling, they will be less susceptible to export downstream. This
reduces the level of nutrient loading off-site.

**F~CYCLING~ = The lesser of: ( V~STRATA~ + V~CANOPY~ )/2
[or]{.underline} V~TURNOVER~**

**3. F~ORGANIC~ - Long-term Storage of Organic Carbon**

**Definition:** The storage of organic carbon in the living and dead
biomass above the soil and within the soil profile.

**Effects On-site:** The net effect of carbon storage is long-term
retention in persistent biomass and in organic matter in the soil
profile.

**Effects Off-site:** Nutrients are held on-site and are less
susceptible to transport.

**F~ORGANIC~ = ( V~CU_FT~ + V~TURNOVER~ + V~SOIL_OM~ )/3**

**4. F~PLANT~ - Maintain Characteristic Plant Community**

**Definition:** Species composition and physical characteristics of
living plant biomass. The emphasis is on the dynamics and structure of
plant community as revealed by the dominant species of trees, shrubs,
saplings, and ground cover, and by the physical characteristics of
vegetation.

**Effects On-site:** Converts solar radiation and carbon dioxide into
complex organic compounds that provide energy to drive food webs.
Provides seeds for regeneration. Provides habitat for nesting, resting,
refuge, and escape cover for animals. Creates micro-climatic conditions
that support completion of life histories of plants and animals.
Provides organic matter for soil development and soil related nutrient
cycling processes. Creates both long- and short- term habitat for
resident or migratory animals.

**Effects off-site:** Provides a source of propagules to maintain
species composition and/or structure of adjacent wetlands and supplies
propagules for colonization of nearby degraded systems. Provides food
and cover for animals from adjacent ecosystems. Provides corridors
(migratory pathways) between habitats, enhances species diversity and
ecosystem stability, and provides habitat and food for migratory and
resident animals.

**F~PLANT~** = (V~COMP~ + V~STRATA~ + V~TURNOVER~ + V~CANOPY~ +
V~MATURITY~)/5

**5. F~HABITAT~** **- Maintain Wildlife Habitat Structure**

**Definition:** The capacity of a wetland to support animal populations
and guilds by providing characteristic habitats.

**Effects On-site:** Provides potential feeding, resting, and nesting
sites for vertebrates and invertebrates. Regulates and moderates
fluctuations in temperature. Provides characteristic habitat to support
a diverse assemblage of organisms dependent upon this wetland type.
Affects all ecosystem processes.

**Effects Off-site:** Provides habitat heterogeneity to landscape,
provides habitat for wide-ranging and migratory animals, provides a
corridor for gene flow between separated populations, and allows progeny
to exploit new areas.

**F~HABITAT~ = ( V~%\_PONDED\ +~ V~SNAGS\ +~ V~COMP\ +~ V~STRATA\ +~
V~MATURITY~ )/5**

**6. F~CONNECT~- Maintain Habitat Interspersion, Quality, and
Connectivity**

**Definition:** The capacity for all organisms to be provided with
diverse and contiguous areas of food and cover.

**Effects On-site:** Provides maintenance of habitat, species, and gene
pool diversity.

**Effects Off-site:** Provides habitat heterogeneity to landscape,
provides habitat for wide-ranging and migratory animals, provides a
corridor for gene flow between separated populations, and allows progeny
to exploit new areas.

**F~HABITAT~ = \[( V~MATURITY~ )2 + V~CONTIG~ + V~MIGRATE~ + V~CONNECT~
\]/5**

**WORKSHEETS FOR SCORING WETLAND FUNCTION VARIABLES**

1.  This functional assessment procedure should only be performed after
    the Minimal Effect Exemption Worksheet has been completed.

2.  **For variables which require a sample plots**, use [Table
    1]{.underline} to determine the [minimum]{.underline} number of
    samples needed. In addition, a sample plot should be taken in each
    of the vegetative communities that in the evaluation area. Plots
    will be 1/5^th^ acre in size (52.7 ft. circle radius). A weighted
    average of the total number of plots taken will be calculated to
    determine the appropriate score.

3.  The U.S. Army Corps of Engineers 1987 Wetland Determination Manual
    50:20 Rule will be used to determine the dominant plant species in
    each vegetative community.

4.  The terms "restoration possible" and "restoration not possible"
    reflects [both]{.underline} the actual physical ability of a site to
    be or to not be restored, **[AND]{.underline}** the management
    decisions being made by the landowner. For example, if a proposed
    conversion site is a Farmed Wetland (FW), this site is rated
    "restoration [not]{.underline} possible" because the landowners
    present farming practices do not allow for restoration of the site
    to a fully functioning wetland.

Table 1

  ------------------------------------ ----------------------------------
  If area in acres is:                 Number of Sampling Points

  Less than 40                         1 per acre

  41-80                                20 + .5(area)

  81-200                               40 + .25(area)
  ------------------------------------ ----------------------------------

**V1** **V~DURATION~**

Indication that the wetland can pond water \>7 days. For this indicator
to apply the landform must be capable of ponding water.

The entire evaluation will be considered for this variable. **Field
indicators** include (Check all that apply):

bare soil areas due to inundation

-   obligate hydrophytic vegetation

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-   water stained leaves

-   direct observation (inundation)

-   sediment deposits

-   bare soils areas due to inundation

-   aerial photography

-   water marks

-   mucky surface layer or thin muck layer on surface

-   drift lines

-   soil survey data

A. Four or more indicators are present or direct observation can
document 7 days of ponding. 1.0

B. Three or more indicators are present. 0.75

C. Two indicators are present. 0.50

D. One indicator is present. 0.25

C. Hydrology has been altered to prevent or reduce ponding. Examples 0.1

include evidence of surface ditches, tile drains, and fill. Restoration
is possible.

E. Restoration is not possible to due site constraints. 0.0

**V2** **V~%PONDED~**

Variable is scored by measurement or estimate of the extent of ponding
on the wetland surface which indicates ponding for \>7 days. The
variable is also used in Habitat Function #2 as an indicator of canopy
gap. The entire evaluation will be considered for this variable.

A. \>50% of area is ponded. 1.0

B. 10-50% of area is ponded. 0.5

C. \<10% of area is ponded. 0.1

D. No evidence of ponding. Restoration not possible. 0.0

**V3 V~DRAIN~ - Subsurface/Surface Drainage of the Wetland**

This variable applies to the portion of the wetland being investigated.
Consult significantly altered 1987 COE Manual and NRCS Bulletin for
background information. NOTE: Drainage structures must have been
installed before Dec. 23, 1985 for consideration of altered hydrology.

A. Hydrology has not been significantly altered by drainage structures .
1.0

B. Wetland hydrology has been modified by drainage structures but the
site 0.5

is not considered significantly altered (includes FW and FWP).

C. Wetland hydrology has been modified by drainage structures, and the
site is considered 0.1

to be significantly altered. This also includes Prior Converted wetland
(PC). Restoration is possible.

D. Evaluation area is such that restoration is not possible. 0.0

**V4 V~SOILQ~ - Soil Conditions of Wetland**

Select Conditions that Most Closely Describe Wetland Soils. Note:
conditions are for a moist soil, not wet or dry.

  ------------------------ ------------------------ ----------------- -------
  Description                                       Soil              Score
                                                    Characteristics   

  A. Soil has conditions   Little or no evidence    Surface horizon   1.0
  approximating those of   that the soil has been   is friable with   
  an undisturbed soil      compacted or rutted by   well defined      
  profile for that soil    grazing, tillage or      structure for the 
  type.                    other mechanical         soil involved     
                           equipment.                                 

  B. Soil profile is       Evidence grazing,        Not as friable or 0.50
  disrupted enough to      farming or other         well structured   
  reduce water movement    disturbance with some    as item A but     
  within the soil profile. compaction of the soil   less compaction   
                           profile or rutting.      than item C.      

  C. Soil profile is so    Obvious evidence of      Platy structure   0.1
  disrupted that normal    grazing, farming or      in the surface    
  water movement within    other disturbance. With  horizon or upper  
  the profile is unlikely  compaction, rutting by   subsoil caused by 
  to occur.                machinery, and/or        compaction. Well  
                           heavily trampled by      formed plow pan   
                           livestock.               may be evident.   

  D. Paved, feed lot, or   Normal water movement    N/A               0.0
  other artificial         within the soil profile                    
  surface.                 cannot occur.                              
  ------------------------ ------------------------ ----------------- -------

**V5** **V~STRATA~**

Mature forested wetlands are usually vertically stratified. Four strata
are typically found in mature mineral flat forests. Forest organisms are
primarily associated with a specific strata. Differences in structure
between sites likely represent differences in animal composition between
the sites as well. More spatially stratified communities often contain
more species.

**NOTE:** If an aggressive exotic (such as Multiflora rose, Tartarian
honeysuckle, Amur honeysuckle, Japanese honeysuckle, Autumn olive,
Garlic mustard, Purple loosestrife etc.) is one of the dominant species
using the 50/20 rule, the strata is not counted as being present. The
entire evaluation area will be considered for this variable.

A. Four vegetative strata present (trees, shrubs, vines, and
herbaceous). 1.0

B. Three vegetative strata present. 0.75

C. Two vegetative strata present. 0.5

D. One perennial vegetative strata present. 0.25

E. Area converted to row crop agriculture; restoration is possible. 0.1

F. Area converted to row crop agriculture; restoration not possible. 0.0

**V6** **V~CANOPY~**

This is a measure of the continuity of the upper layers of the forest
canopy. It is assumed the more complete the canopy cover the more
efficient the wetland is at nutrient cycling regardless of the maturity
of the stand. Stands with canopy coverage of 80-100% provide optimal
habitat for forest wildlife. An appropriate number of sample plots will
be taken to calculate the final score for this variable.

A. Tree canopy cover \>80%. 1.0

B. Tree canopy cover 50-80%. 0.5

C. Tree canopy 10-50% 0.25

D. Site is not forested or has a tree canopy \<10% potential for
recovery (includes sites dominated by shrubs) 0.1

E. No tree canopy; no potential for recovery (site not suited for trees)
0.0

**V7** **V~TURNOVER~**

Detrital stocks are represented by down and dead woody debris, and
organic debris on the forest floor. Standing stocks of detritus are
assumed to be proportional to annual turnover. Stocks down and dead
woody debris, leaf litter and humus layers (o horizon). Most of the
annual nutrient cycling occurs at the surface and subsurface levels,
therefore, organic debris found on the ground as coarse woody debris and
as part of the soil profile are indicative of the active biomass
fraction and are representative of annual detrital turnover in the
system. An appropriate number of sample plots will be taken to calculate
the final score for this variable. Indicators include:

-   Downed and dead woody debris

-   Leaf litter layer

-   Humus layers (O horizon)

-   Snags

A. Three indicators are present. 1.0

B. Two indicators are present. 0.50

C. One indicator is present. 0.25

D. Area barren of woody debris potential for recovery. 0.1

E. Area barren of all elements; no potential for recovery. 0.0

**V8 V~CU_FT~**

The amount of organic carbon stored in the living biomass above the soil
is estimated by calculating the cubic feet of wood present. Basal area
and total tree height sampled within the evaluation area will be used to
calculate the biomass in cubic feet of wood including bole, limbs, and
branches. An appropriate number of sample plots will be taken to
calculate the final score for this variable. Formula, Cu. Ft. = \[(A X
B)/3\] X 10, A = no. of trees using a 10 factor prism, B = ave. tree
height

A. Cubic feet of woody biomass \>2000 cu. ft./acre. 1.0

B. Cubic feet of woody biomass 1000-2000 cu. ft./acre. 0.5

C. Cubic feet of woody biomass \<1000 cu. ft./acre. 0.1

D. No woody biomass present. 0.0

**V9 V~SOIL_OM~**

This variable is defined as the weighted average of organic matter (OM)
content of the upper 6 inches of the soil profile. An appropriate number
of sample plots will be taken to calculate the final score for this
variable.

A. Soil OM content is \>3%. 1.0

B. Soil OM content is 1-3%. 0.5

C. Soil OM content is \<1%. 0.1

D. No soil OM present. 0.0

**V10** **V~COMP~**

Native tree species typical for this forest type (excluding willow
species) are present to fully stock the site, e.g. the site would be
considered as forested (also includes seedlings). This variable well be
calculated using an average for the site if applicable. The 50/20 rule
will be used.

An appropriate number of sample plots will be taken to calculate the
final score for this variable.

A ≥4 species are present. 1.0

B. 3 species are present. 0.75

C. 2 species are present, res. 0.50

D. 1 species is present. 0.25

E. Site is not fully stocked with trees e.g. cropland, pasture, idle
land etc. 0.1

F. Restoration is not possible. 0.0

**V11** **V~MATURITY~**

Standing and mature or dying trees provide nesting habitat for a variety
of animal species, including invertebrates, birds, reptiles, amphibians,
and mammals. Mature trees provide a significant amount of food for
wildlife species as well as leaf/woody debris for the nutrient cycle. An
appropriate number of sample plots will be taken to calculate the final
score for this variable. Note: To qualify for A-D the site should be
fully stocked with trees and considered forestland.

A. [\>]{.underline}5 trees/ac. [\>]{.underline}16 inches DBH 1.0

B. 2-4 trees/ac. [\>]{.underline}16 inches DBH [or,]{.underline} 0.75

[\>]{.underline}5 trees/ac. [\>]{.underline}12 inches DBH

C. \>30 trees/ac. \>6 inches DBH 0.5

D. \>300 stems/ac (including trees, shrubs, and seedlings) 0.25

E. Few or no trees present; restoration possible, e.g. ag. land. Also
includes sites with scattered trees. 0.1

Note: when V10, E is selected V11 E is to be used.

F. No trees present; restoration not possible. 0.0

**V12** **V~SNAGS~**

This variable is defined as the density of standing dead trees (\>5
inches DBH and \>6 feet tall). Standing dead trees (snags) are a normal
component of forested wetlands. The density of standing dead trees
relates to the suitability of a site as wildlife habitat due to the
large number of species that forage on, and nest and den in snags. It
may also provide an insight into the hydrology of the site. More
standing dead tress than a typical site might show an increase in
ponding on the site. See [Table 1]{.underline} to determine the required
number of sample points.

NOTE: The number of snags listed below are [per acre]{.underline}. For
example, a 0.2 acre site with 1 snag translates into 5 snags per acre.

A. \>5 snags/ac. 1.0

B. 2-5 snags/ac. 0.5

C. 1 snags/ac. 0.25

D. No snags, restoration possible. 0.1

E. No snags present; restoration not possible. 0.0

**V13 V~MIGRATE\ ~**

This variable considers that small woodlots (3-5 acres) are important as
migratory stop over sites for forest-interior bird species. Acreage for
this variable includes the wetland and contiguous woodland associated
with the wetland.

Area calculations can be made directly from an NWI or topographic map,
or from aerial photos.

A. \>5 acre woodlot. 1.0

B. 3 - 5 acre woodlot. 0.5

C. 2 - 3 acre woodlot. 0.1

D. 2 \< acre woodlot. 0.0

**V14** **V~CONTIG\ ~**

Heterogeneity in distribution and abundance of organisms is inherent at
all scales in every natural ecosystem. Any measure of ecosystem
attributes must consider the appropriate scale and sample size in which
to measure those attributes in order to understand ecosystem processes.
Patchiness of vegetation (lack of contiguous cover types) affects the
types and abundance of trophic interactions, energy flow, and
competitive interactions of animals. These processes in turn affect
animal populations.

A. The wetland is part of a larger block (\>40 acres) of contiguous
upland and/or 1.0

wetland forest which is non-fragmented and has few non-natural breaks.

B. Wetland is part of a 30-40 acre block as above. 0.75

C. Wetland is part of a 20-30 acre block as above. 0.5

D. Wetland is part of a 10-20 acre block as above. 0.25

E. Wetland is part of a block \<10 acres, or is part of a highly
fragmented larger 0.1

block; restoration is possible. Include PC that and non wetlands.

F. Wetland is part of a block \<10 acres, or is part of a highly
fragmented larger 0.0

block: restoration is [not]{.underline} possible (Example: urban area).

**V15 V~CONNECT\ ~**

This variable is defined as the distance from the wetland's perimeter to
other "suitable" habitat for wildlife. Many species of wildlife that are
common inhabitants of forested wetlands also may use other habitat such
as upland forests.

This variable is assessed by measuring the distance from the wetland to
other types of wetlands, to upland forest habitat, or to other
communities capable of providing habitat for at least some of the
species typically associated with forested wetlands. At least 20% of the
perimeter of the wetland being evaluated must meet the described
distance measurements. Minimize size of woods to be connected to is 3
acres.

A. A direct connection of continuous woody or shrubby cover ≥50' in
width is present. 1.0

Examples include hedge rows, fence rows, windbreaks, etc.

B. A direct connection of continuous woody or shrubby cover 50'\< in
width is present. 0.75

Examples include hedge rows, fence rows, windbreaks, etc.

C. A direct connection does not exist, but suitable habitat is \<1/4
mile from 0.50

the wetland perimeter..

D. A direct connection does not exist, but suitable habitat is 1/4-1/2
mile 0.25

from the wetland perimeter.

E. A direct connection does not exist, but suitable habitat is \>1/2 0.1

from the wetland perimeter. Include PC that and non wetlands.

F. Site cannot be restored, e.g. urban land etc. 0.0