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.
MLRA notes
Major Land Resource Area (MLRA): 032X–Northern Intermountain Desertic Basins
Major land resource area (MLRA):
032X – Northern Intermountain Desertic Basins – This MLRA is comprised of two major Basins, the Big Horn and Wind River. These two basins are distinctly different and are split by LRU’s to allow individual ESD descriptions. These warm basins are surrounded by uplifts and rimmed by mountains, creating a unique set of plant responses and communities. Unique characteristics of the geology and geomorphology single these two basins out.
Further information regarding MLRAs, refer to: United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. Available electronically at: http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_053624#handbook.
LRU notes
Land Resource Unit (LRU):
32X01A (WY): This LRU is the Big Horn Basin within MLRA 32. This LRU is lower in elevation, slightly warmer and receives slightly less overall precipitation than the Wind River Basin (LRU 02). This LRU was originally divided into two LRU's - LRU A which was the core and LRU B which was the rim. With the most current standards, this LRU is divided into two Subsets. This subset is Subset A, referred to as the Core, which is warm, dry eroded basin floor. As the LRU shifts outer edges, aspect and relation to the major bodies of water and taller landforms create minor shifts in soil chemistry influencing the variety of ecological sites and plant interactions. The extent of soils currently correlated to this ecological site does not fit within the digitized boundary. Many of the noted soils are provisional and will be reviewed and corrected in mapping update projects. Other map units are correlated as small inclusions within other MLRA’s/LRU’s based on elevation, landform, and biological references. Older ESD's will refer to LRU A. LRU A and LRU 01 in MLRA 32X are synonymous.
Moisture Regime: Typic Aridic, prior to 2012, there are map units that cross over to ustic aridic or ustic aridic was correlated into this core area. As progressive mapping continues and when the ability to do update projects, these overlapping map units will be corrected.
Temperature Regime: Mesic
Dominant Cover: Rangeland, with Saltbush flats the dominant vegetative cover for this LRU/ESD.
Representative Value (RV) Effective Precipitation: 5-9 inches (127 – 229 mm)
RV Frost-Free Days: 110-150 days
Classification relationships
Relationship to Other Established Classification Systems:
National Vegetation Classification System (NVC):
3 Xeromorphic Woodland, Scrub & Herb Vegetation Class
3.B Cool Semi-Desert Scrub & Grassland Subclass
3.B.1 Cool Semi-Desert Scrub & Grassland formation
3.B.1.NE Western North American Cool Semi-Desert Scrub & Grassland Division
M169 Great Basin & Intermountain Tall Sagebrush Shrubland & Steppe Macrogroup
G302 Artemisia Tridentata - Artemisia tripartita - Purshia tridentata Big Sagebrush Steppe Group
CEGL001535 - Artemisia tridentata ssp. wyomingensis/Pseudoroegneria spicata Herbaceous Vegetation or
CEGL001009 - Artemisia tridentata ssp. wyomingensis/Pseudoroegneria spicata Shrubland
Ecoregions (EPA):
Level I: 10 North American Deserts
Level II: 10.1 Cold Deserts
Level III: 10.1.18 Wyoming Basin
Level IV: 10.1.18.g Big Horn Salt Desert Shrub Basin
Ecological site concept
• Site receives no additional water.
• Slope is < 50%
• Soils are:
o Textures range from sand to fine sandy loam in top 4” (10 cm) of mineral soil surface
o All subsurface horizons have a weighted average of <18% clay.
o Shallow (10-20+ in. (25-50+ cm)
o Not skeletal (<35% rock fragments) within 20” (50 cm) of mineral soil surface
o Non-saline, sodic, or saline-sodic
Sandy (Sy) 5-9” Big Horn Basin Precipitation Zone,
Sandy sites are found in common with sandstone outcroppings, escarpments and ridges; down slope where soils have developed or weathered out further Sandy sites are prevalent.
Annual precipitation and modeled relative effective annual precipitation ranges from 5 to 9 inches (127 – 229 mm). The normal precipitation pattern shows peaks in May and June and a secondary peak in September. The noted peaks account for approximately 50% of the mean annual precipitation. Much of the moisture that falls in the latter part of the summer is lost by evaporation and much of the moisture that falls during the winter is lost by sublimation.
Average snowfall is about 20 inches annually. Wide fluctuations may occur in yearly precipitation and result in more dry years than those with more than normal precipitation. Temperatures show a wide range between summer and winter and between daily maximums and minimums, due to the high elevation and dry air, which permits rapid incoming and outgoing radiation. Cold air outbreaks from Canada in winter move rapidly from northwest to southeast and account for extreme minimum temperatures. Chinook winds may occur in winter and bring rapid rises in temperature. Extreme storms may occur during the winter, but most severely affect ranch operations during late winter and spring. High winds are generally blocked from the basin by high mountains but can occur in conjunction with an occasional thunderstorm.
Growth of native cool-season plants begins approximately on April 1st and continues through to July 1st. Cool weather and moisture in September may produce some green up of cool season plants that will continue to late October. For detailed information visit the Natural Resources Conservation Service National Water and Climate Center at http://www.wcc.nrcs.usda.gov/. “Basin”, "Emblem", "Greybull", “Lovell”, "Worland FAA AP" and “Worland” are the representative weather stations for LRU A. The following graphs and charts are a collective sample representing the averaged normals and 30-year annual rainfall data for the selected weather stations from 1981 to 2010.
Table 3. Representative climatic features
Frost-free period (characteristic range)
110-115 days
Freeze-free period (characteristic range)
131-142 days
Precipitation total (characteristic range)
7-8 in
Frost-free period (actual range)
105-119 days
Freeze-free period (actual range)
130-150 days
Precipitation total (actual range)
6-8 in
Frost-free period (average)
112 days
Freeze-free period (average)
138 days
Precipitation total (average)
7 in
Characteristic range
Actual range
Bar
Line
Figure 1. Monthly precipitation range
Characteristic range
Actual range
Bar
Line
Figure 2. Monthly minimum temperature range
Characteristic range
Actual range
Bar
Line
Figure 3. Monthly maximum temperature range
Bar
Line
Figure 4. Monthly average minimum and maximum temperature
Figure 5. Annual precipitation pattern
Figure 6. Annual average temperature pattern
Climate stations used
(1) WORLAND [USW00024062], Worland, WY
(2) WORLAND [USC00489770], Worland, WY
(3) BASIN [USC00480540], Basin, WY
(4) GREYBULL [USC00484080], Greybull, WY
(5) EMBLEM [USC00483031], Burlington, WY
(6) LOVELL [USC00485770], Lovell, WY
Influencing water features
The characteristics of these upland soils have no influence from ground water (water table below 60 inches (150 cm)) and have minimal influence from surface water/overland flow. There may be isolated features that are affected by snow pack that persists longer than surrounding areas due to position on the landform (shaded/protected pockets). No streams are classified within this ecological site.
Soil features
The soils of this site are shallow (10”-20” to bedrock) well to excessively well-drained soils formed in eolian deposits or alluvium over residuum or residuum. These soils have rapid to very rapid permeability and may occur on all slopes. The bedrock may be of any kind except igneous or volcanic and is virtually impenetrable to plant roots. Thin ineffectual layers of other soil textures are disregarded. The soil characteristics having the most influence on the plant community are the shallow depths and light textures which can affect the available moisture.
Major Soil Series correlated to this site include: Oceanet
Table 4. Representative soil features
Parent material
(1) Residuum–sandstone (2) Alluvium–interbedded sedimentary rock (3) Eolian deposits
Surface texture
(1) Loamy fine sand
(2) Fine sandy loam
(3) Sandy loam
(4) Sand
(5) Loamy sand
Family particle size
(1) Sandy
Drainage class
Well drained to excessively drained
Permeability class
Rapid to very rapid
Depth to restrictive layer
10–20 in
Soil depth
10–20 in
Available water capacity (0-40in)
0.4–3 in
Calcium carbonate equivalent (0-40in)
10%
Electrical conductivity (0-40in)
2 mmhos/cm
Sodium adsorption ratio (0-40in)
Not specified
Soil reaction (1:1 water) (0-40in)
7.4–8.4
Subsurface fragment volume <=3" (Depth not specified)
10%
Ecological dynamics
Potential vegetation on this site is dominated by mid cool-season perennial grasses. Other significant vegetation includes sagebrushes and a variety of forbs and shrubs. The expected potential composition for this site is about 75% grasses, 10% forbs and 15% woody plants. The composition and production will vary naturally due to historical use, fluctuating precipitation and fire frequency.
As this site deteriorates, species such as threadleaf sedge, blue grama, and big sagebrush will increase. Plains pricklypear and weedy annuals will invade. Cool season grasses such as needleandthread, rhizomatous wheatgrasses, and Indian ricegrass will decrease in frequency and production.
The Historic Climax Plant Community (description follows the plant community diagram) has been determined by study of rangeland relic areas, or areas protected from excessive disturbance. Trends in plant communities going from heavily grazed areas to lightly grazed areas, seasonal use pastures, and historical accounts have also been used.
The following is a State and Transition Model Diagram that illustrates the common plant communities (states) that can occur on the site and the transitions between these communities. The ecological processes will be discussed in more detail in the plant community narratives following the diagram.
State 1 Needleandthread/Indian Ricegrass Plant Community
Community 1.1 Needleandthread/Indian Ricegrass Plant Community
The interpretive plant community for this site is the Historic Climax Plant Community. This state evolved with grazing by large herbivores, soils less than 15 inches in depth, and periodic fires. The cyclical nature of the fire regime in this community and the shallow soils prevented big sagebrush from being the dominant landscape. Cool season midgrasses dominate the state. Potential vegetation is about 75% grasses or grass-like plants, 10% forbs, and 15% woody plants. It is found on areas that are properly managed with grazing and/or prescribed burning, and sometimes on areas receiving occasional short periods of rest.
The major grasses include needleandthread, rhizomatous wheatgrasses, Indian ricegrass, and bluebunch wheatgrass. Other grasses occurring on the state include Sandberg bluegrass, and threadleaf sedge. A variety of forbs and shrubs also occur in this state and plant diversity is high (see Plant Composition Table).
The total annual production (air-dry weight) of this state is about 325 pounds per acre, but it can range from about 200 lbs. /acre in unfavorable years to about 400 lbs. /acre in above average years.
The state is stable and well adapted to the Northern Intermountain Desertic Basins climatic conditions. The diversity in plant species allows for high drought resistance. This is a sustainable plant community (site/soil stability, watershed function, and biologic integrity).
Transitions or pathways leading to other plant communities are as follows:
• Moderate, Continuous Season-Long grazing will convert the plant community to the Perennial Grass/Mixed Shrub Plant Community. Prolonged drought will exacerbate this transition.
Figure 7. Annual production by plant type (representative values) or group (midpoint values)
Figure 8. Plant community growth curve (percent production by month). WY0501, 5-9BH Upland sites. Monthly percentages of total annual growth for all upland sites with dominantly C3 Cool season plants..
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
J
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A
M
J
J
A
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15
50
20
5
10
State 2 Perennial Grass/Mixed Shrub Plant Community
Community 2.1 Perennial Grass/Mixed Shrub Plant Community
Historically, this plant community evolved under grazing and a low fire frequency. Currently, it is found under moderate, season-long grazing by livestock and will be exacerbated by prolonged drought conditions. In addition, the fire regime for this site has been modified and extended periods without fire is now common. This plant community is still dominated by cool-season grasses, while short warm-season grasses and miscellaneous forbs account for the balance of the understory.
The overstory is comprised of a variety of shrubs.
The dominant grasses include needleandthread, rhizomatous wheatgrasses, threadleaf sedge, Sandberg bluegrass, and blue grama. Forbs commonly found on the site include badlands mule’s-ear, waxleaf penstemon, little larkspur, sulfur flower buckwheat, fleabane, and lemon scurfpea. Shrubs can make up to 25% of the annual production. These include big sagebrush, silver sagebrush, shadscale saltbush, and rabbitbrushes. The overstory of shrubs and understory of grass and forbs provide a diverse plant community.
When compared to the Historic Climax Plant Community, bluebunch wheatgrass and Indian ricegrass have decreased. Plains pricklypear cactus may have invaded, but occurs only in small patches. Threadleaf sedge, blue grama, big sagebrush, rabbitbrushes and a variety of forbs have increased. Total production is less as the mid cool season grasses are replaced with short warm season grasses.
The total annual production (air-dry weight) of this state is about 200 pounds per acre, but it can range from about 75 lbs. /acre in unfavorable years to about 300 lbs. /acre in above average years.
The herbaceous component is mostly intact and plant vigor and replacement capabilities are sufficient. Water flow patterns and litter movement may be occurring but only on steeper slopes. Incidence of pedestalling is minimal. Soils are mostly stable and the surface shows minimum soil loss. The communities’ soil, biotic integrity and watershed is intact, although more than normal runoff may occur due to the sod forming vegetation and bare ground.
Transitional pathways leading to other plant communities are as follows:
• Prescribed grazing or possibly long-term prescribed grazing will return this plant community to the HCPC. The probability of this occurring is high especially if rotational grazing along with short deferred grazing is implemented as part of the prescribed method of use. In addition, the removal of fire suppression will allow a somewhat natural fire regime to reoccur to more easily transition between this plant community and the HCPC. A prescribed fire treatment can be useful to hasten this transition if desired; however, this may require a removal of grazing for a period of time to build a surplus of fine fuels.
• Frequent and Severe grazing on very coarse soils will convert this state to the Mixed Shrub/Blowout Dune Plant Community.
• Frequent and Severe grazing on less coarse soils will convert this state to the Threadleaf Sedge Sod Plant Community.
Figure 9. Plant community growth curve (percent production by month). WY0501, 5-9BH Upland sites. Monthly percentages of total annual growth for all upland sites with dominantly C3 Cool season plants..
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
J
F
M
A
M
J
J
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15
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State 3 Mixed Shrub/Blowout Dune Plant Community
Community 3.1 Mixed Shrub/Blowout Dune Plant Community
This plant community is the result of frequent and severe grazing and protection from fire. Shrubs eventually dominate this vegetative state as the annual production of shrubs will exceed 25%. Areas of bare sand also can dominate this site as wind scouring and deposition can occur and modify the soil surface. Yucca on coarser soils can also be a major part of this plant community. These shrub species are a significant component of the plant community and the preferred cool season grasses have been eliminated or greatly reduced.
The dominant grasses are Sandberg bluegrass, threadleaf sedge, and blue grama. Weedy annual species such as cheatgrass may occupy the site if a seed source is available. Patches of pricklypear cactus can be noticeable. Shrubs such as big and silver sagebrushes, rabbitbrushes, and a variety of forbs have increased significantly. Plant diversity is moderate to poor. The interspaces between plants have expanded leaving the amount of bare ground more prevalent. When compared to the HCPC, grass production and available forage has diminished significantly, but the total production is compensated by the increase in shrub production.
The total annual production (air-dry weight) of this state is about 125 pounds per acre, but it can range from about 50 lbs. /acre in unfavorable years to about 200 lbs. /acre in above average years.
This plant community is relatively resistant to change. Continued frequent and severe grazing does not seem to affect the plant composition or structure of the plant community. These areas are more resistant to fire as less fine fuels are available and the bare ground between the shrub plants is increased. Plant diversity is poor. Production is reduced and plant vigor is diminished due to blowing sand, which can defoliate the vegetative parts of the grass plants.
The soils are exposed to wind as erosion is accelerated and blowouts increase. Pedestalling is pervasive and eolian deposits (dunes) form around the clumped vegetation. This situation is normally extensive.
Transitions or pathways leading to other plant communities are as follows:
• Reseeding with mulch and/or no use or very long-term prescribed grazing, is necessary to return a protective vegetation cover to this state so as to convert this to the Near HCPC conditions. No use may return protective vegetation cover to the site or possible prescribed grazing that may take generations, may also accomplish this goal. The grazing prescription most commonly used is complete deferment during the growing season, with limited use in the winter. This will provide as much plant litter cover as possible to protect the soil surface.
Figure 10. Plant community growth curve (percent production by month). WY0501, 5-9BH Upland sites. Monthly percentages of total annual growth for all upland sites with dominantly C3 Cool season plants..
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
J
F
M
A
M
J
J
A
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O
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15
50
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5
10
State 4 Threadleaf Sedge Sod Plant Community
Community 4.1 Threadleaf Sedge Sod Plant Community
This plant community can occur as a result of frequent and severe grazing on less coarse soils.
Rabbitbrushes, and possibly yucca may remain significant components of the plant community, but a dense stand of threadleaf sedge is established. Pricklypear cactus can also become established in dense patches.
Grasses of importance are needleandthread, Sandberg bluegrass and blue grama. Patches of annuals such as cheatgrass and other weedy annual forbs such as halogeton, Russian thistle, and kochia, will persist on this site, if not treated. The interspaces between plants will have diminished in size.
When compared with the HCPC or the Perennial Grass/Mixed Shrub Plant Communities, the annual production is less. Some of the climax grasses, such as Indian ricegrass, may not be present.
The total annual production (air-dry weight) of this state is about 150 pounds per acre, but it can range from about 50 lbs. /acre in unfavorable years to about 250 lbs. /acre in above average years.
This sod is some what resistant to change under moderate grazing and the reestablishment of perennial mid and tall grasses is difficult in this situation. The biotic integrity of this state is minimally functional and plant diversity is moderate to low.
Erosion has been diminished as the sodded areas are resistant to wind erosive processes. Pedestalling is apparent along the sod edges.
Transitional pathways leading to other plant communities are as follows:
• Grazing land mechanical treatment (seeding, etc.), brush management if necessary, and continued prescribed grazing, will return this plant community to near Historic Climax Plant Community. Any chiseling or disturbance in the sod should be implemented carefully so as not to create large openings, which can expose the soil to wind erosion.
Figure 11. Plant community growth curve (percent production by month). WY0501, 5-9BH Upland sites. Monthly percentages of total annual growth for all upland sites with dominantly C3 Cool season plants..
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
J
F
M
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M
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J
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15
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10
Additional community tables
Table 5. Community 1.1 plant community composition
Wildlife Interpretations
Historic Climax Plant Community: The predominance of grasses in this plant community favors grazers and mixed-feeders, such as bison, elk, and antelope. Suitable thermal and escape cover for deer may be limited due to the low quantities of woody plants. However, topographical variations could provide some escape cover. When found adjacent to sagebrush dominated states, this plant community may provide brood rearing/foraging areas for sage grouse, as well as lek sites. Other birds that would frequent this plant community include western meadowlarks, horned larks, and golden eagles. Many grassland obligate small mammals would occur here.
Perennial Grass/Mixed Shrub Plant Community: The combination of a shrub overstory and an understory of grasses and forbs provide a very diverse plant community for wildlife. This diversity provides important winter ranges, so mule deer and antelope may use this state for foraging and cover year-round, as would cottontail and jack rabbits. It provides important winter, nesting, brood-rearing, and foraging habitat for sage grouse.
Mixed Shrub/Blowout Dune Plant Community: These communities provide limited foraging for antelope and other grazers. They may be used as a foraging site by sage grouse if proximal to woody cover and if the Historic Climax Plant Community or the Perennial Grass/Mixed Shrub Plant Community is limiting. Generally, these are not target plant communities for wildlife habitat management.
Threadleaf Sedge Sod Plant Community: This plant community can provide important winter foraging for elk, mule deer and antelope. This community provides excellent escape and thermal cover for large ungulates, as well as nesting habitat for sage grouse.
Animal Community – Grazing Interpretations
The following table lists suggested stocking rates for cattle under continuous season-long grazing under normal growing conditions. These are conservative estimates that should be used only as guidelines in the initial stages of the conservation planning process. Often, the current plant composition does not entirely match any particular plant community (as described in this ecological site description). Because of this, a field visit is recommended, in all cases, to document plant composition and production. More precise carrying capacity estimates should eventually be calculated using this information along with animal preference data, particularly when grazers other than cattle are involved. Under more intensive grazing management, improved harvest efficiencies can result in an increased carrying capacity. If distribution problems occur, stocking rates must be reduced to maintain plant health and vigor.
Plant Community Production Carrying Capacity*
(lb. /ac) (AUM/ac)
Historic Climax Plant Community 200-400 .10
Perennial Grass/Mixed Shrub 75-300 .08
Mixed Shrub/Blowout Dune 35-200 .03
Threadleaf Sedge Sod 50-250 .05
* - Continuous, season-long grazing by cattle under average growing conditions.
Grazing by domestic livestock is one of the major income-producing industries in the area. Rangeland in this area may provide yearlong forage for cattle, sheep, or horses. During the dormant period, the forage for livestock use needs to be supplemented with protein because the quality does not meet minimum livestock requirements.
Hydrological functions
Water is the principal factor limiting forage production on this site. This site is dominated by soils in hydrologic group B and C. Infiltration ranges from rapid to very rapid. Runoff potential for this site varies from low to moderate depending on soil hydrologic group and ground cover. In many cases, areas with greater than 75% ground cover have the greatest potential for high infiltration and lower runoff. An example of an exception would be where short-grasses form a strong sod and dominate the site. Areas where ground cover is less than 50% have the greatest potential to have reduced infiltration and higher runoff (refer to Part 630, NRCS National Engineering Handbook for detailed hydrology information).
Rills and gullies should not typically be present. Water flow patterns should be barely distinguishable if at all present. Pedestals are only slightly present in association with bunchgrasses. Litter typically falls in place, and signs of movement are not common. Chemical and physical crusts are rare to non-existent. Cryptogamic crusts are present, but only cover 1-2% of the soil surface.
Recreational uses
This site provides hunting opportunities for upland game species. The wide varieties of plants which bloom from spring until fall have an esthetic value that appeals to visitors.
Wood products
No appreciable wood products are present on the site.
Other products
None noted.
Supporting information
Inventory data references
Information presented here has been derived from NRCS inventory data. Field observations from range trained personnel were also used. Other sources used as references include: USDA NRCS Water and Climate Center, USDA NRCS National Range and Pasture Handbook, and USDA NRCS Soil Surveys from various counties.
Inventory Data References
Data Source Number of Records Sample Period State County
SCS-RANGE-417 19 1965-1986 WY Park & others
Approval
Scott Woodall, 9/05/2019
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)
Ray Gullion
Contact for lead author
ray.gullion@wy.usda.gov
Date
05/02/2008
Approved by
Marji Patz
Approval date
Composition (Indicators 10 and 12) based on
Annual Production
Indicators
Number and extent of rills:
Rills should not be present
Presence of water flow patterns:
Barely observable
Number and height of erosional pedestals or terracettes:
Essentially non-existent
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are
not bare ground):
Bare ground is 40-60% occurring in small areas throughout site
Number of gullies and erosion associated with gullies:
Active gullies should be restricted to areas of concentrated water flow patterns on steeper slopes
Extent of wind scoured, blowouts and/or depositional areas:
Small scoured sites may be observed
Amount of litter movement (describe size and distance expected to travel):
Litter movement is little to none based on topography and water flow patterns
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range
of values):
Plant cover and litter is at 50% or greater of soil surface and maintains soil surface integrity. Soil Stability class is anticipated to be 3 or greater.
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Use Soil Series description for depth and color of A-horizon
Effect of community phase composition (relative proportion of different functional groups) and spatial
distribution on infiltration and runoff:
Grass canopy and basal cover should reduce raindrop impact and slow overland flow providing increased time for infiltration to occur. Infiltration is rapid to very rapid
Presence and thickness of compaction layer (usually none; describe soil profile features which may be
mistaken for compaction on this site):
No compaction layer or soil surface crusting should be present.
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:
Mid stature Bunch Grasses
Sub-dominant:
Mid Stature Rhizomatous Grasses Shrubs
Other:
Short grasslikes = Short grasses Forbs
Additional:
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or
decadence):
Very Low
Average percent litter cover (%) and depth ( in):
Average litter cover is 15-25% with depths of 0.1 to 0.2 inches
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
250 lbs/ac
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:
Threadleaf sedge, Blue grama, Big sagebrush, Silver sagebrush, Green rabbitbrush, skunkbush sumac, Badlands mules-ear, Prickly Pear, Broom Snakeweed, Unpalatable forbs, Annuals, Exotics, and Species found on Noxious Weed List
The Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.
Click on box and path labels to scroll to the respective text.
