Natural Resources
Conservation Service

Ecological site R070BC017NM

Bottomland

Accessed: 08/10/2026

Home / esd CATALOG / MLRA 070B / ecological site R070BC017NM

USC

Metric

General information

Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.

Click to explore map

Figure 1. Mapped extent

Areas shown in blue indicate the maximum mapped extent of this ecological site. Other ecological sites likely occur within the highlighted areas. It is also possible for this ecological site to occur outside of highlighted areas if detailed soil survey has not been completed or recently updated.

Table 1. Dominant plant species

Tree	Not specified
Shrub	Not specified
Herbaceous	Not specified

Download full description

Physiographic features

This site occurs on broad valleys, flood plains or basins at the lowest position in relation to adjacent landscapes. They are derived from mixed alluvium for sandstone, shale and limestone. It is found at the mouth of intermittent drainages or draws. Slopes are level to nearly level, averaging less than 3 percent. Elevations range from 2,842 to 4,000 feet.

Table 2. Representative physiographic features

Landforms	(1) Alluvial flat (2) Valley floor (3) Basin floor
Flooding duration	Very brief (4 to 48 hours) to brief (2 to 7 days)
Flooding frequency	Rare to frequent
Ponding frequency	None
Elevation	2842 – 4000 ft
Slope	1 – 3 %
Aspect	Aspect is not a significant factor

Climatic features

The climate of the area is “semi-arid continental”. The average annual precipitation ranges from 8 to 13 inches. Variations of 5 inches, more or less, are common. Over 80 percent of the precipitation falls from April through October. Most
of the summer precipitation comes in the form of high intensity – short duration thunderstorms.

Temperatures are characterized by distinct seasonal changes and large annual and diurnal temperature changes. The average annual temperature is 61 degrees with extremes of 25 degrees below zero in the winter to 112 degrees in the summer.

The average frost-free season is 207 to 220 days. The last killing frost is in late March or early April, and the first killing frost is in late October or early November.

Temperature and rainfall both favor warm season perennial plant growth. In years of abundant spring moisture, annual forbs and cool season grasses can make up an important component of this site. This site receives overflow from heavy summer rains periodically. Occasionally water will stand on the surface for short periods. When this happens frequently, or when water stands for longer periods, only the plants that can tolerate inundation, such as giant sacaton, will survive. During drought periods or when long periods occur between overflows, a variety of plants will move in and establish on the site.

Table 3 Representative climatic features

Frost-free period (average)	220 days
Freeze-free period (average)	240 days
Precipitation total (average)	10 in

Bar

Line

Figure 2. Monthly precipitation range

Bar

Line

Figure 3. Monthly average minimum and maximum temperature

Soil features

The soils of this site are deep and very deep. Surface textures are loamy fine sand, very fine sandy loam, fine sandy loam, sandy loam, silty loam, loam, clay loam or silty clay loam. The underlying layers may be loam, silt loam, clay loam, silty clay loam, sandy loam, fine sandy loam or loamy fine sand. These soils may have thin stratas of sand, silt, clay, very fine sand or very fine sandy loam. The soils have rapid to moderately slow permeability.

Minimum and maximum values listed below represent the characteristic soils for this site.

Characteristic Soils:
Glendale
Bippus
Bigetty
Largo
Harkey
Pecos
Pima
Dev
Pima Varient

Table 4. Representative soil features

Surface texture	(1) Loamy fine sand (2) Loam (3) Fine sandy loam
Family particle size	(1) Loamy
Drainage class	Moderately well drained to well drained
Permeability class	Moderately slow to rapid
Soil depth	72 in
Surface fragment cover <=3"	0 – 10 %
Surface fragment cover >3"	0 – 1 %
Available water capacity (0-40in)	3 – 8 in
Calcium carbonate equivalent (0-40in)	3 – 15 %
Electrical conductivity (0-40in)	0 – 4 mmhos/cm
Sodium adsorption ratio (0-40in)	0 – 5
Soil reaction (1:1 water) (0-40in)	7.4 – 8.4
Subsurface fragment volume <=3" (Depth not specified)	0 – 15 %
Subsurface fragment volume >3" (Depth not specified)	0 – 1 %

Ecological dynamics

The Bottomland site occurs on broad valleys and flood plains at the lowest positions on the landscape and is subject to periodic flooding. This periodic flooding and deep wetting essentially determine vegetation patterns on this site. The Bottomland site is associated with and often found at the mouth of Draw sites. The potential plant community exhibits a tall grass aspect largely dominated by giant sacaton. Soil drying due to overgrazing, gullying, and redirection or blockage of water flow may cause the transition to a tobosa-dominated state. A state dominated by burrograss may result due to continued loss of tobosa, erosion, and soil surface sealing—especially on silt loam and silty clay loam textured surface soils. A mesquite-dominated state may result from the loss of grass cover and dispersal of mesquite seed. Saltcedar may invade in response to changes in the historical flow regimes and the introduction of its seed—especially along stream channels or on soils adjacent to areas with a high water table.

State and transition model

Custom diagram

Standard diagram

More interactive model formats are also available. View Interactive Models

More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective text

State 1
Historic Climax Plant Community

Community 1.1
Historic Climax Plant Community

Bottomland Grassland: The historic plant community is principally dominated by giant sacaton. Some additional grass species representative of this site include alkali sacaton, tobosa, vine mesquite, plains bristlegrass, and twoflower trichloris. Fourwing saltbush and mesquite are two of the more common shrubs associated with this site, but in the historic community they are sparsely scattered across the site. Giant sacaton has the capability to produce large amounts of aboveground biomass, which provides important forage for livestock and helps to slow runoff, increase infiltration, and protect the site from erosion. Grazing in the spring, deferring grazing in the fall, or during dry summers, can maximize forage production.4 Mowing giant sacaton during the summer may improve forage quality and accessibility while minimizing negative effects on production.3 Fire has produced mixed results depending on time of year and fire intensity. Several growing seasons may be required for giant sacaton to recover pre-burn production levels. Overgrazing, drought, or fire can cause a decrease in giant sacaton, vine mesquite, alkali sacaton, plains bristlegrass, and twoflower trichloris. A sparser, less vigorous sacaton community may result. Continued loss of grass cover increases erosion, effectively drying the site causing the transition to an alternate grassland state (Tobosa Grassland).

Diagnosis: Giant sacaton is the dominant grass. Grass cover is uniform. Litter cover is high, and bare patches are few and less than 2 m in length. Shrubs are sparse, averaging less than three percent canopy cover.

Figure 4. Annual production by plant type (representative values) or group (midpoint values)

Table 5. Annual production by plant type

Plant type	Low (lb/acre)	Representative value (lb/acre)	High (lb/acre)
Grass/Grasslike	2125	3188	4250
Shrub/Vine	200	300	400
Forb	175	262	350
Total	2500	3750	5000

Table 6. Ground cover

Tree foliar cover	0%
Shrub/vine/liana foliar cover	0%
Grass/grasslike foliar cover	40-40%
Forb foliar cover	0%
Non-vascular plants	0%
Biological crusts	0%
Litter	40-50%
Surface fragments >0.25" and <=3"	0%
Surface fragments >3"	0%
Bedrock	0%
Water	0%
Bare ground	20-20%

Figure 5. Plant community growth curve (percent production by month). NM2817 , R042XC017NM Bottomland HCPC. R042XC017NM Bottomland HCPC Warm Season Plant Community.

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	10	10	25	30	15	5	0	0

State 2
Tobosa Grassland

Community 2.1
Tobosa Grassland

Additional States:

Tobosa Grassland: This state is characterized by the predominance of tobosa. On fine-textured
soils that receive surface run-in water, tobosa may attain dense almost pure stands. On drier sites
that receive less water due to gullying, or due to decreased infiltration, associated with loss of
grass cover, tobosa occurs in scattered patches with large areas of bare ground. Burrograss is the
sub-dominant species. In the absence of grazing, tobosa tends to stagnate and accumulates large
amounts of standing dead material. Rotational grazing, or burning during years with adequate
precipitation following fire may help to maximize tobosa production and forage quality.1,12
Burning during years with below average precipitation may limit increases in tobosa yield the
first year following fire.6

Diagnosis: Tobosa is the dominant grass species. Grass cover is variable (depending on the
degree of site degradation) ranging from uniform to patchy.

Transition to Tobosa Grassland (1a) The transition to a tobosa-dominated community is
believed to result from decreased available soil moisture due to the redirection or blockage of
run-in water, gullying, or overgrazing. Roads or other physical barriers on site or off site may
cause the redirection or blockage of run-in water. Reduction of overland flow and decreased
residence time of stand water may favor tobosa dominance. Tobosa is favored by sites that
receive periodic flooding, but cannot withstand extended periods of inundation. Overgrazing
increases runoff rates and gully formation, reduces infiltration, effectively drying the site. Sites
with finer textured soils may have a greater susceptibility for dominance by tobosa. 12

Key indicators of approach to transition:
Decreased vigor and cover of giant sacaton
Increase in the amount of tobosa
Reduced overland flow and residence time of standing water
Formation of gullies or deepening of existing channels

Transition back to Bottomland Grassland (1b) The natural hydrology of the site must be
restored. Culverts, turnouts, or rerouting roads may help re-establish natural overland flow, if
roads or trails have blocked or altered the flow of run-in water. Erosion control structures or
shaping and filling gullies may help regain natural flow patterns and establish vegetation if the
flow has been channeled. Prescribed grazing will help establish proper forage utilization and
maintain grass cover and litter necessary to protect the site from accelerated erosion.

State 3
Burrograss Grassland

Community 3.1
Burrograss Grassland

Burrograss Grassland: Burrograss is the dominant species. Tobosa is typically present in
varying amounts, usually in patches or clumps occupying the more moist depressions. Burrograss
ranks poor as a forage grass, but begins growth early and is used to some extent when young and
green. Burrograss is favored by calcareous fine textured soils and spreads by seed and stolons. It
produces large amounts of seed with wiry awns that help in dissemination, and in augering the
hardened callus (tip of the seed) into the soil. The ability of burrograss to auger into soils enables
it to establish and expand on bare soils prone to crust over with physical and biological crusts.

Diagnosis: Burrograss is the dominant grass species. Grass cover is variable ranging from patchy
to very patchy. Large bare areas are present and interconnected. Physical crusts are present and
may occupy most of the bare areas.

Transition to Burrograss Grassland (2a) Loss of grass cover, decreased soil moisture, soil
surface sealing, and erosion enable this transition. As grass cover declines, organic matter and
infiltration decrease. Erosion increases, removing soil and nutrients from bare areas, which
results in soil sealing. Burrograss produces substantial amounts of viable seed and is one of the
few grasses able to maintain, and even increase, on bottomland soils that are sealed by biological
and physical crusts.

Key indicators of approach to transition:
Decrease in cover of tobosa
Increased amount of bare ground
Increased evidence of physical and biological crusts.

Transition back to Tobosa Grassland (2b) Erosion control structures may help regain natural
overland flow and increase vegetation cover (see transition1b above). Re-establishing grass cover
will further decrease erosion and increase infiltration. Breaking up physical crusts by soil
disturbance may promote infiltration and seedling emergence. Seeding may be necessary if
inadequate seed source remains. Prescribed grazing will help establish proper forage utilization
and maintain grass cover.

State 4
Mesquite-Dominated

Community 4.1
Mesquite-Dominated

Mesquite-Dominated State:
This state is characterized by the dominance of mesquite, and by accelerated erosion. Grass cover
is variable, but typically patchy.

Diagnosis: Mesquite is the dominant species in aspect and composition. Grass cover is typically
patchy with large, interconnected bare areas present. Giant sacaton and alkali sacaton are absent
or restricted to small patches. Tobosa or burrograss are the dominant grasses on this site. Rills
and gullies may be common and actively eroding.

Transition to Mesquite-Dominated (3a, 4, 5) The reasons for different pathways in transitions
to a mesquite-dominated state versus a tobosa or burrograss grassland with few shrubs are not
known. Dispersal of shrub seed, persistent loss of grass cover, and competition between shrubs
and remaining grasses for resources may drive this transition. Loss of grass cover reduces
infiltration, decreasing available soil moisture necessary for grass seedling establishment. Reduced soil moisture may favor mesquite establishment and survival. Accelerated erosion due
to loss of grass cover can relocate organic matter and nutrients from shrub interspaces, and
concentrate them around shrub bases.14 This relocation of resources further increases the shrubs
competitive advantage.

Key indicators of approach to transition:
Increase in size and frequency of bare patches.
Loss of grass cover in shrub interspaces.
Increased signs of erosion.

Transition back to Bottomland Grassland (3b) Erosion control methods such as shaping and
filling gullies, net wire diversions, rock and brush dams, etc. may be needed to curtail erosion
and restore site hydrology. Brush control will be necessary to overcome competition between
shrubs and grass seedlings. Seeding may expedite recovery or may be necessary if an adequate
seed source is no longer remaining. Prescribed grazing will help ensure adequate deferment and
proper forage utilization following grass establishment. The degree to which this site is capable
of recovery depends on the restoration of hydrology, the extent of degradation to soil resources,
and adequate rainfall necessary to establish grasses.

State 5
Saltcedar State

Community 5.1
Saltcedar State

Saltcedar State: Saltcedar is an aggressive invader that typically invades on fine-textured soils
where its roots can reach the water table, but once established it can survive without access to
ground water. It reaches maximum density where the water table is from 1.5 to 6 m deep, and
forms more open stands where the water table is deeper. 9,10 Saltcedar is a prolific seed producer.
It is resistant to fire, periods of inundation with water, salinity, and re-sprouts following cutting.
Saltcedar can also increase soil salinity by up-taking salts and concentrating them in its leaves
and subsequent shedding of the leaves to the soil surface.

Diagnosis: This state is characterized by the presence of saltcedar. Saltcedar cover is variable
ranging from sparse to dense. Densities may depend on such variables as depth to ground water,
timing and duration of flood events, and soil texture and salinity. Grass cover varies in response
to saltcedar density.

Transition to Saltcedar State (6a) It is not know if this transition occurs only on saline affected
soils, or if it can occur on non-saline sites. Salty Bottomland sites typically have a higher
susceptibility to the invasion of saltcedar. The invasion of saltcedar is associated with saline
soils, the presence of saltcedar on adjacent sites and dispersal of its seed, and disturbance to
existing vegetation or hydrology. Saltcedar propagules must be present to invade and establish on
bottomland sites. Disturbance such as fire, grazing, or drought may facilitate the establishment of
saltcedar by decreasing the vigor of native vegetation and providing bare areas for saltcedar
seedling establishment with minimal competition. Changes in seasonal timing, rate and volume
of run-in water may facilitate the establishment of saltcedar on Bottomland sites.8 Damming
rivers has reduced flow volume and caused shifts in the timing of peak flow from spring to
summer. The reduced flows have increased fine sediments, creating the ideal conditions for
saltcedar seedling establishment. Summer water discharges provide water at times consistent
with saltcedar seed production. Increases in salinity due to return of irrigation water to streams and ditches may also support the establishment of saltcedar. (This transition should also possible
from the Tobosa-Grassland and Burrograss-Grassland states).

Key indicators of approach to transition:
Increase in size and frequency of bare patches.
Changes in timing and volume of peak discharge
Increased soil salinity
Presence of saltcedar propagules

Transition back to Bottomland Grassland (6b) Saltcedar control is costly and often labor
intensive. Control programs utilizing herbicide, or herbicide in conjunction with mechanical
control or prescribed fire have proven effective in some instances. 5,7,11 Without restoring
historical flow regimes, extensive follow-up management may be necessary to maintain the
bottomland grassland.13

Additional community tables

Table 7. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)
Grass/Grasslike
1				2438–2625
	big sacaton	SPWR2	Sporobolus wrightii	2438–2625	–
2				263–375
	tobosagrass	PLMU3	Pleuraphis mutica	263–375	–
	alkali sacaton	SPAI	Sporobolus airoides	263–375	–
3				263–375
	vine mesquite	PAOB	Panicum obtusum	263–375	–
	plains bristlegrass	SEVU2	Setaria vulpiseta	263–375	–
4				113–188
	cane bluestem	BOBA3	Bothriochloa barbinodis	113–188	–
	white tridens	TRAL2	Tridens albescens	113–188	–
	false Rhodes grass	TRCR9	Trichloris crinita	113–188	–
5				113–188
	Grass, perennial	2GP	Grass, perennial	113–188	–
Shrub/Vine
6				113–188
	fourwing saltbush	ATCA2	Atriplex canescens	113–188	–
7				38–113
	honey mesquite	PRGL2	Prosopis glandulosa	38–113	–
8				38–113
	Apache plume	FAPA	Fallugia paradoxa	38–113	–
	American tarwort	FLCE	Flourensia cernua	38–113	–
	littleleaf sumac	RHMI3	Rhus microphylla	38–113	–
9				38–113
	Shrub (>.5m)	2SHRUB	Shrub (>.5m)	38–113	–
Forb
10				75–188
	coyote gourd	CUPA	Cucurbita palmata	75–188	–
	common sunflower	HEAN3	Helianthus annuus	75–188	–
	broadleaved pepperweed	LELA2	Lepidium latifolium	75–188	–
	globemallow	SPHAE	Sphaeralcea	75–188	–
11				75–188
	Forb (herbaceous, not grass nor grass-like)	2FORB	Forb (herbaceous, not grass nor grass-like)	75–188	–

Table 8. Community 2.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 9. Community 3.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 10. Community 4.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 11. Community 5.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Interpretations

Animal community

This site provides habitats which support a resident animal community that is characterized by black-tailed jackrabbit, yellow-faced pocket gopher, coyote, meadowlark, mourning dove, scaled quail, sparrow hawk, Western spadefoot toad and Western diamondback rattlesnake. Where this site includes riparian vegetation along the Pecos and Black rivers, the resident animal community is characterized by raccoon, gray fox, muskrat, red-winged blackbird, summer tanager, ferruginous hawk, mourning dove, Gambel’s quail, killdeer, tree lizard, Eastern fence lizard, tiger salamander, leopard frog, bullfrog and checkered garter shake.

Most resident birds and Bullock’s oriole, blue grosbeak, painted bunting, Swainson’s hawk and mourning dove nest. Where aquatic macrophytes occur, yellow-throated warbler nest. Sandhill crane and long-billed curlew winter along the Pecos River and American avocet and blacknecked stilt utilize this site during migration. The golden eagle utilizes larger trees for roosting and occasionally, nesting.

Hydrological functions

The runoff curve numbers are determined by field investigations using hydraulic cover conditions and hydrologic soil groups.

Hydrologic Interpretations
Soil Series----- Hydrologic Group
Bippus---------- B
Bigetty--------- C
Glendale-------- B
Harkey---------- B
Largo----------- B
Pima------------ B
Dev------------- A
Pecos----------- D/B

Recreational uses

This site offers recreation potential for hiking, nature observation and photography in addition to antelope, quail and dove hunting.

Natural beauty is enhanced by the constrast between this lush vegetated site and the drier, more barren sites which surround it.

Wood products

This site has no real potential for wood products. Where woody species have increased, they can be used for curiosities or small furniture.

Other products

This site is well suited for all kinds and classes of livestock, during all seasons of the year. It is best suited for cows during the growing season. Periodic removal of excess coarse stalk material by burning, shredding or mowing every other year will help to keep new growth avaialble to livestock. Burning, if practiced, should be done in late winter or early spring when soil surface moisture is present. Retrogression is characterized by a decrease in vine-mesquite and vigor of giant sacaton. Alkali sacaton, plains bristlegrass and twoflower trichloris decrease. This causes an increase in tobosa to a point of being a colony type of vegetation. Continued retrogression can cause severe water erosion that can destroy the potential of this site.

Other information

Guide to Suggested Initial Stocking Rate Acres per Animal Unit Month
Similarity Index - Ac/AUM
100 - 76---------- 1.0 – 2.3
75 – 51----------- 2.0 – 3.3
50 – 26----------- 3.4 – 6.0
25 – 0------------ 6.1 - +

Supporting information

Other references

Literature References:
1. Britton, C. M., A.A. Steuter. 1983. Production and nutritional attributes of tobosagrass
following burning. Southwestern Naturalist. 28(3): 347-352.

2. Canfield, R.H. 1939. The effect and intensity and frequency of clipping on density and yield
of black grama and tobosa grass. U.S. Dept. Agr. Tech. Bul. 681, 32 pp.

3. Cox, J.R. 1988. Seasonal burning and mowing impacts on Sporobolus wrightii grasslands.
J. Range. Manage. 41:12-15.

4. Cox, J.R., R.L.Gillen, and G.B. Ruyle. 1989. Big sacaton riparian grassland management:
Seasonal grazing effects on plant and animal production. Applied Agricultural
Research. 4(2): 127-134

5. Duncan, K. W. 1994. Saltcedar: establishment, effects, and management. Wetland Journal
6(3):10-13.

6. Dwyer, D. D. 1972. Burning and nitrogen fertilization of tobosa grass. NM State Univ
Agric. Exp. Station Bull No 595. Las Cruces, NM: New Mexico State University. 8 p.

7. Egan, T. B. 1997. Afton Canyon riparian restoration project: fourth year status report.
Presentation at tamarisk and Russian olive workshop, September, 1997, Grand Junction, CO.

8. Everitt. B. L. 1980. Ecology of saltcedar – a plea for research. Environmental
Geology 3:77-84.

9. Horton, J. S., F. C. Mounts, and J. M. Kraft. 1960. Seed germination and seedling
establishment of phreatophytic species. Research Paper RM-48. USDA-Forest Service, Rocky Mountain
Forest and Range Experiment Station, Ft. Collins, CO.

10. Horton, J. S. and C. J. Campbell. 1974. Management of phreatophytic and riparian
vegetation for maximum multiple use values. Research Paper RM-117, USDA-Forest
Service, Rocky Mountain Forest and Range Experiment Station, Ft. Collins, CO.

11. Neill, W. M. 1990. Pp. 91-98, In: M. R. Kunzmann, R. R. Johnson and P. S. Bennett (eds.)
Tamarisk control in southwestern United States. Proceedings of Tamarisk Conference, University of
Arizona, Tucson, AZ, September 23-3, 1987. Special Report No. 9. National Park Service, Cooperative
National Park Resources Studies Unit, School of Renewable Natural Resources, University of Arizona,
Tucson, AZ.

12. Paulsen, H.A., Jr. and F.N. Ares. 1962. Grazing values and management of black grama and
tobosa grasslands and associated shrub ranges of the Southwest. U. S. Dept. Agr. Tech. Bul. 1270,
Washington DC. 56 pp.

13. Smith S. D. and D. A. Devitt. 1996. Physiological ecology of saltcedar: why is it a
successful invader? Presentation at Saltcedar Management and Riparian Restoration Workshop, Las Vegas,
NV, September, 1996.

14. U.S. Department of Agriculture, Natural Resources Conservation Service. 2001. Soil
Quality Information Sheets. Rangeland Soil Quality—Erosion. Rangeland Sheet 9 & 10 [Online].
Available: http://www.statlab.iastate.edu/survey/SQI/range.html

Contributors

David Trujillo
Don Sylvester

Rangeland health reference sheet

Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.

Author(s)/participant(s)
Contact for lead author
Date
Approved by
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
Presence of water flow patterns:
Number and height of erosional pedestals or terracettes:
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Number of gullies and erosion associated with gullies:
Extent of wind scoured, blowouts and/or depositional areas:
Amount of litter movement (describe size and distance expected to travel):
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):

Dominant:

Sub-dominant:

Other:

Additional:
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Average percent litter cover (%) and depth ( in):
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
Perennial plant reproductive capability:

Download reference sheet

Natural ResourcesConservation Service