Natural Resources
Conservation Service
Ecological site R043BY168WY
Steep Loamy High Mountains
Accessed: 11/13/2024
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.
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.
Associated sites
R043BY122WY |
Loamy High Mountains Loamy |
---|---|
R043BY130WY |
Overflow High Mountains Overflow |
R043BY162WY |
Shallow Loamy High Mountains Shallow Loamy |
Similar sites
R043BY122WY |
Loamy High Mountains Loamy (Ly) 20+M has higher production, occurs on lesser sloping topography, and lacks some of the forb diversity. |
---|
Table 1. Dominant plant species
Tree |
Not specified |
---|---|
Shrub |
Not specified |
Herbaceous |
Not specified |
Physiographic features
This site occurs on moderate to steep mountain slopes. It is found on all exposures at high elevations, but primarily on north and east slopes at lower elevations.
Table 2. Representative physiographic features
Landforms |
(1)
Hill
(2) Alluvial fan (3) Stream terrace |
---|---|
Flooding frequency | None |
Ponding frequency | None |
Elevation | 6,500 – 12,000 ft |
Slope | 15 – 70% |
Ponding depth |
Not specified |
Climatic features
Annual precipitation is fairly evenly distributed through the year and averages over 20 inches. Snows are heavy and usually remain in place during the winter. Annual snowfall averages 150 to 200 inches per year. 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. This is predominantly due to the high elevation and dry air, which permits rapid incoming and outgoing radiation. Cold air outbreaks in winter move rapidly from northwest to southeast and account for extreme minimum temperatures.
Prevailing winds are from the southwest, and strong winds are less frequent than over other areas of Wyoming. Occasional storms, however, can bring brief periods of high winds with gusts exceeding 50 mph.
Growth of native cool season plants begins about June 1 at lower elevations, as late as July 15 at higher elevations, and continues until the beginning of September.
The following information is from the “Moran 5 WNW” climate station:
Minimum Maximum 5 yrs. out of 10 between
Frost-free period (days): 31 78 June 30 – August 24
Freeze-free period (days): 65 118 June 5 – September 9
Annual Precipitation (inches): <20.78 >29.35 (2 years in 10)
Mean annual precipitation: 25.23 inches
Mean annual air temperature: 36.5?F (22.1?F Avg. Min. to 50.9?F Avg. Max.)
For detailed information visit the Natural Resources Conservation Service National Water and Climate Center at http://www.wcc.nrcs.usda.gov/cgibin/state.pl?state=wy website. Other climate station representative of this precipitation zone include ”Alta 1 NW”, “Lake Yellowstone”, “Moose”, “Old Faithful”, and “Snake River” in Teton County; “Bedford 3 SE” in Lincoln County; and “Bondurant” in Sublette County.
Table 3. Representative climatic features
Frost-free period (average) | 78 days |
---|---|
Freeze-free period (average) | 118 days |
Precipitation total (average) | 29 in |
Influencing water features
Soil features
The soils of this site are moderately deep (greater than 20" to bedrock) to very deep and well-drained with textures ranging from very fine sandy loams through clay loams. Some soils have a lime horizon below 3 feet. The overlying soil is usually noncalcareous. These sites occur on slopes >30% and usually on north and east aspects.
Table 4. Representative soil features
Surface texture |
(1) Gravelly loam (2) Clay loam (3) Fine sandy loam |
---|---|
Family particle size |
(1) Loamy |
Drainage class | Moderately well drained to well drained |
Permeability class | Moderately slow to moderate |
Soil depth | 20 – 60 in |
Surface fragment cover <=3" | 20% |
Surface fragment cover >3" | Not specified |
Available water capacity (0-40in) |
2.5 – 6 in |
Calcium carbonate equivalent (0-40in) |
15% |
Electrical conductivity (0-40in) |
8 mmhos/cm |
Sodium adsorption ratio (0-40in) |
5 |
Soil reaction (1:1 water) (0-40in) |
6.6 – 8.4 |
Subsurface fragment volume <=3" (Depth not specified) |
10% |
Subsurface fragment volume >3" (Depth not specified) |
5% |
Ecological dynamics
As this site deteriorates because of a combination of frequent and severe grazing, species such as three-tip and mountain big sagebrush, buckwheat, and yarrow will increase. Rhizomatous and/or less palatable grasses such as Letterman needlegrass, rhizomatous wheatgrass, and Sandberg bluegrass increase. Kentucky bluegrass may invade. Cool-season grasses such as bluebunch wheatgrass, Idaho fescue, Columbia needlegrass, and spike fescue will decrease in frequency and production.
Mountain big sagebrush will become dominant with the absence of fire. Wildfires are often actively controlled so chemical control using herbicides has replaced the historic role of fire on this site. Recently, prescribed burning has regained some popularity.
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 and transition model
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 submodel, plant communities
State 2 submodel, plant communities
State 3 submodel, plant communities
State 4 submodel, plant communities
State 1
Mixed Grass/Mixed Shrub Plant Community (HCPC)
Community 1.1
Mixed Grass/Mixed Shrub Plant Community (HCPC)
The interpretive plant community for this site is the Historic Climax Plant Community. This state evolved with grazing by large herbivores and is well suited for grazing by domestic livestock. Potential vegetation is estimated at 75% grasses or grass-like plants, 15% forbs, and 10% woody plants. The major grasses include bluebunch wheatgrass, Idaho fescue, Columbia needlegrass, thickspike wheatgrass, and spike fescue. Other grasses may include big, Canby, mutton, and Sandberg bluegrass, blue wildrye, prairie junegrass, bottlebrush squirreltail, Letterman needlegrass, alpine timothy, timber oatgrass, slender and bearded wheatgrass, and mountain and nodding brome. Woody species may include mountain big sagebrush, chokecherry, rose, snowbrush ceanothus, three-tip sagebrush, bitterbrush, snowberry, serviceberry, silver sagebrush, and green rabbitbrush. A typical plant composition for this state consists of bluebunch wheatgrass 25-35%, Idaho fescue 15-20%, Columbia needlegrass 10-20%, thickspike wheatgrass 10-20%, spike fescue 10-20%, other grasses and grass-like plants 10-20%, perennial forbs 5-15%, and 5-15% woody species. Ground cover, by ocular estimate, varies from 55-60%. The total annual production (air-dry weight) of this state is about 2200 lbs./acre, but it can range from about 1800 lbs./acre in unfavorable years to about 2600 lbs./acre in above average years. The following is the growth curve of this plant community expected during a normal year: Growth curve number: WY0101 Growth curve name: 20+M, UPLAND SITES Growth curve description: ALL UPLAND SITES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 0 0 0 0 5 30 40 20 5 0 0 0 (Monthly percentages of total annual growth) This plant community is extremely stable and well adapted to the Central Rocky Mountains climatic conditions. The diversity in plant species allows for high drought tolerance. 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: • Nonuse and No Fire will convert this plant community to the Mountain Big Sage/Bunchgrass State. • Heavy Continuous Season-long Grazing and No Fire will convert this plant community to the Mountain Big Sage/Idaho Fescue State. • Wildfire with Heavy Continuous Season-long Grazing will convert this plant community to the Three-tip Sage State.
Figure 2. Annual production by plant type (representative values) or group (midpoint values)
Figure 3. Plant community growth curve (percent production by month). WY0101, 20+ upland sites.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
---|---|---|---|---|---|---|---|---|---|---|---|
J | F | M | A | M | J | J | A | S | O | N | D |
5 | 30 | 40 | 20 | 5 |
State 2
Mountain Big Sage/Bunchgrass Plant Community
Community 2.1
Mountain Big Sage/Bunchgrass Plant Community
This plant community is the result of long-term protection from grazing and fire. Mountain big sagebrush dominates the site, often exceeding 20-50% annual production and lowering herbaceous forage production. Bunchgrasses such as bluebunch wheatgrass, blue wildrye, Columbia needlegrass, Idaho fescue, and mountain brome dominate the understory. The total annual production (air-dry weight) of this state is about 2000 pounds per acre, but it can range from about 1600 lbs./acre in unfavorable years to about 2400 lbs./acre in above average years. The following is the growth curve of this plant community expected during a normal year: Growth curve number: WY0101 Growth curve name: 20+M, UPLAND SITES Growth curve description: ALL UPLAND SITES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 0 0 0 0 5 30 40 20 5 0 0 0 (Monthly percentages of total annual growth) The state is stable and protected from excessive erosion. The biotic integrity of this plant community is usually intact, however forage value will decrease and wildlife values will shift toward different species. The watershed is functioning. Transitional pathways leading to other plant communities are as follows: • Prescribed Fire followed by deferment for 1 to 2 years as part of a Prescribed Grazing plan will return this state to near Historic Climax Plant Community (Mixed Grass/Mixed Shrub State). Care should be taken when planning brush management to consider wildlife habitat and critical winter ranges. • Brush Management or Wildfire followed by Heavy Continuous Season-long Grazing will convert this plant community to the Three-tip Sage State.
Figure 4. Plant community growth curve (percent production by month). WY0101, 20+ upland sites.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
---|---|---|---|---|---|---|---|---|---|---|---|
J | F | M | A | M | J | J | A | S | O | N | D |
5 | 30 | 40 | 20 | 5 |
State 3
Mountain Big Sage/Idaho Fescue Plant Community
Community 3.1
Mountain Big Sage/Idaho Fescue Plant Community
This plant community is the result of heavy, continuous season-long grazing and protection from fire. Mountain big sagebrush eventually dominates this plant community with its annual production often exceeding 50%. Forbs such as yarrow, phlox, lupine, larkspur, buckwheat, and pussytoes increase. Grasses such as Idaho fescue, Sandberg and mutton bluegrass, Letterman needlegrass, and rhizomatous wheatgrass increase in proportion to other grasses. The total annual production (air-dry weight) of this state is about 1500 pounds per acre, but it can range from about 1000 lbs./acre in unfavorable years to about 2000 lbs./acre in above average years. The following is the growth curve of this plant community expected during a normal year: Growth curve number: WY0101 Growth curve name: 20+M, UPLAND SITES Growth curve description: ALL UPLAND SITES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 0 0 0 0 5 30 40 20 5 0 0 0 (Monthly percentages of total annual growth) Soil erosion is accelerated because of increased bare ground. The biotic community has been compromised, but is relatively stable. The watershed is functioning, but is at risk of further degradation. Water flow patterns and pedestals are obvious. Infiltration is reduced and runoff is increased. Transitional pathways leading to other plant communities are as follows: • Prescribed Fire followed by deferment for 1 to 2 years as part of a Prescribed Grazing plan will return this state to near Historic Climax Plant Community (Mixed Grass/Mixed Shrub State). Care should be taken when planning brush management to consider wildlife habitat and critical winter ranges. • Brush Management or Wildfire followed by Heavy Continuous Season-long Grazing will convert this plant community to the Three-tip Sage State.
Figure 5. Plant community growth curve (percent production by month). WY0101, 20+ upland sites.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
---|---|---|---|---|---|---|---|---|---|---|---|
J | F | M | A | M | J | J | A | S | O | N | D |
5 | 30 | 40 | 20 | 5 |
State 4
Three-tip Sage Plant Community
Community 4.1
Three-tip Sage Plant Community
This plant community is the result of brush management or wildfire followed by improper grazing management practices. With sagebrush removed, it is dominated by sprouting shrubs such as green rabbitbrush and three-tip sagebrush. Rhizomatous wheatgrasses, low growing bunchgrasses such as Letterman needlegrass and Sandberg bluegrass, and unpalatable annual and perennial forbs dominate the herbaceous understory. Forbs such as prairie smoke, lupine, and thistles are common. There is a substantial amount of bare ground. The total annual production (air-dry weight) of this state is about 1000 pounds per acre, but it can range from about 500 lbs./acre in unfavorable years to about 1500 lbs./acre in above average years. The following is the growth curve of this plant community expected during a normal year: Growth curve number: WY0101 Growth curve name: 20+M, UPLAND SITES Growth curve description: ALL UPLAND SITES JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC 0 0 0 0 5 30 40 20 5 0 0 0 (Monthly percentages of total annual growth) The soil is not protected and erosion will increase if management is not changed. The biotic integrity may be reduced due to low vegetative production. The watershed is functioning at risk. Transitions or pathways leading to other plant communities are as follows: It is not often practicable or economically feasible to convert this plant community.
Figure 6. Plant community growth curve (percent production by month). WY0101, 20+ upland sites.
Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
---|---|---|---|---|---|---|---|---|---|---|---|
J | F | M | A | M | J | J | A | S | O | N | D |
5 | 30 | 40 | 20 | 5 |
Additional community tables
Table 5. Community 1.1 plant community composition
Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
---|---|---|---|---|---|---|
Grass/Grasslike
|
||||||
1 | 550–770 | |||||
bluebunch wheatgrass | PSSP6 | Pseudoroegneria spicata | 550–770 | – | ||
2 | 330–440 | |||||
Idaho fescue | FEID | Festuca idahoensis | 330–440 | – | ||
3 | 220–440 | |||||
Columbia needlegrass | ACNE9 | Achnatherum nelsonii | 220–440 | – | ||
4 | 220–440 | |||||
spike fescue | LEKI2 | Leucopoa kingii | 220–440 | – | ||
5 | 220–440 | |||||
thickspike wheatgrass | ELLAL | Elymus lanceolatus ssp. lanceolatus | 220–440 | – | ||
6 | 220–440 | |||||
Grass, perennial | 2GP | Grass, perennial | 0–110 | – | ||
Letterman's needlegrass | ACLE9 | Achnatherum lettermanii | 0–110 | – | ||
mountain brome | BRMA4 | Bromus marginatus | 0–110 | – | ||
Porter brome | BRPO2 | Bromus porteri | 0–110 | – | ||
sun sedge | CAINH2 | Carex inops ssp. heliophila | 0–110 | – | ||
California oatgrass | DACA3 | Danthonia californica | 0–110 | – | ||
timber oatgrass | DAIN | Danthonia intermedia | 0–110 | – | ||
squirreltail | ELELE | Elymus elymoides ssp. elymoides | 0–110 | – | ||
blue wildrye | ELGL | Elymus glaucus | 0–110 | – | ||
slender wheatgrass | ELTR7 | Elymus trachycaulus | 0–110 | – | ||
slender wheatgrass | ELTRS | Elymus trachycaulus ssp. subsecundus | 0–110 | – | ||
prairie Junegrass | KOMA | Koeleria macrantha | 0–110 | – | ||
oniongrass | MEBU | Melica bulbosa | 0–110 | – | ||
alpine timothy | PHAL2 | Phleum alpinum | 0–110 | – | ||
Cusick's bluegrass | POCU3 | Poa cusickii | 0–110 | – | ||
muttongrass | POFE | Poa fendleriana | 0–110 | – | ||
Sandberg bluegrass | POSE | Poa secunda | 0–110 | – | ||
spike trisetum | TRSP2 | Trisetum spicatum | 0–110 | – | ||
Forb
|
||||||
7 | 110–330 | |||||
Forb, perennial | 2FP | Forb, perennial | 0–110 | – | ||
common yarrow | ACMI2 | Achillea millefolium | 0–110 | – | ||
giant hyssop | AGAST | Agastache | 0–110 | – | ||
agoseris | AGOSE | Agoseris | 0–110 | – | ||
pussytoes | ANTEN | Antennaria | 0–110 | – | ||
sandwort | ARENA | Arenaria | 0–110 | – | ||
milkvetch | ASTRA | Astragalus | 0–110 | – | ||
balsamroot | BALSA | Balsamorhiza | 0–110 | – | ||
Indian paintbrush | CASTI2 | Castilleja | 0–110 | – | ||
hawksbeard | CREPI | Crepis | 0–110 | – | ||
buckwheat | ERIOG | Eriogonum | 0–110 | – | ||
elkweed | FRSP | Frasera speciosa | 0–110 | – | ||
bedstraw | GALIU | Galium | 0–110 | – | ||
geranium | GERAN | Geranium | 0–110 | – | ||
little sunflower | HEPU3 | Helianthus pumilus | 0–110 | – | ||
stoneseed | LITHO3 | Lithospermum | 0–110 | – | ||
lupine | LUPIN | Lupinus | 0–110 | – | ||
creeping barberry | MARE11 | Mahonia repens | 0–110 | – | ||
bluebells | MERTE | Mertensia | 0–110 | – | ||
ragwort | PACKE | Packera | 0–110 | – | ||
beardtongue | PENST | Penstemon | 0–110 | – | ||
phacelia | PHACE | Phacelia | 0–110 | – | ||
phlox | PHLOX | Phlox | 0–110 | – | ||
buttercup | RANUN | Ranunculus | 0–110 | – | ||
stonecrop | SEDUM | Sedum | 0–110 | – | ||
ragwort | SENEC | Senecio | 0–110 | – | ||
aster | SYMPH4 | Symphyotrichum | 0–110 | – | ||
meadow-rue | THALI2 | Thalictrum | 0–110 | – | ||
clover | TRIFO | Trifolium | 0–110 | – | ||
American vetch | VIAM | Vicia americana | 0–110 | – | ||
violet | VIOLA | Viola | 0–110 | – | ||
mule-ears | WYAM | Wyethia amplexicaulis | 0–110 | – | ||
Shrub/Vine
|
||||||
8 | 110–330 | |||||
Shrub, deciduous | 2SD | Shrub, deciduous | 0–110 | – | ||
Shrub, evergreen | 2SE | Shrub, evergreen | 0–110 | – | ||
Tree, deciduous | 2TD | Tree, deciduous | 0–110 | – | ||
Tree, evergreen | 2TE | Tree, evergreen | 0–110 | – | ||
Saskatoon serviceberry | AMAL2 | Amelanchier alnifolia | 0–110 | – | ||
silver sagebrush | ARCA13 | Artemisia cana | 0–110 | – | ||
threetip sagebrush | ARTR4 | Artemisia tripartita | 0–110 | – | ||
mountain big sagebrush | ARTRV | Artemisia tridentata ssp. vaseyana | 0–110 | – | ||
snowbrush ceanothus | CEVE | Ceanothus velutinus | 0–110 | – | ||
yellow rabbitbrush | CHVI8 | Chrysothamnus viscidiflorus | 0–110 | – | ||
chokecherry | PRVI | Prunus virginiana | 0–110 | – | ||
antelope bitterbrush | PUTR2 | Purshia tridentata | 0–110 | – | ||
Woods' rose | ROWOW | Rosa woodsii var. woodsii | 0–110 | – | ||
snowberry | SYMPH | Symphoricarpos | 0–110 | – |
Interpretations
Animal community
Animal Community – Wildlife Interpretations
Mixed Grass/Mixed Shrub Plant Community (HCPC): This plant community provides suitable thermal and escape cover for mule deer, elk, and antelope. Sagebrush, which can approach 15% protein and 40-60% digestibility, provides important winter forage for mule deer and elk. Birds that would frequent this plant community include horned larks and golden eagles.
Mountain Big Sage/Bunchgrass Plant Community: This plant community may be useful for the same wildlife that would use the Historic Climax Plant Community.
Mountain Big Sage/Idaho Fescue Plant Community: This plant community may be beneficial for the same wildlife that would use the Historic Climax Plant Community. However, the plant community composition is less diverse, and thus, less apt to meet the seasonal needs of these animals.
Three-tip Sage Plant Community: This plant community provides limited forage for elk and mule deer due to low production and lack of palatable woody species.
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)
Mixed Grass/Mixed Shrub (HCPC) 1800-2600 0.6
Mountain Big Sage/Bunchgrass 1600-2400 0.5
Mountain Big Sage/Idaho Fescue 1000-2000 0.3
Three-tip Sage 500-1500 0.15
* - 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, with localized areas in hydrologic groups A and C. Infiltration ranges from rapid to moderate. 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. 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 and shrubs. 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 variety 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.
Supporting information
Inventory data references
Inventory Data References (narrative)
Information presented here has been derived from NRCS clipping data and other inventory data. Field observations from range trained personnel were also used. Those involved in developing this site include: Bill Christensen, Range Management Specialist, NRCS; Karen Clause, Range Management Specialist, NRCS; and Everet Bainter, Range Management Specialist, NRCS. 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
Contributors
K. Clause
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) | K. Clause, E. Bainter |
---|---|
Contact for lead author | karen.clause@wy.usda.gov or 307-367-2257 |
Date | 03/16/2007 |
Approved by | E. Bainter |
Approval date | |
Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
Rare to nonexistent. Where present, short and widely spaced. -
Presence of water flow patterns:
Barely observable. -
Number and height of erosional pedestals or terracettes:
Rare to nonexistent. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Bare ground can range from 0-10%. -
Number of gullies and erosion associated with gullies:
Active gullies should not be present. -
Extent of wind scoured, blowouts and/or depositional areas:
Rare to nonexistent. -
Amount of litter movement (describe size and distance expected to travel):
Herbaceous litter expected to move in moderate amounts. Large woody debris will show only slight movement down slope. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil Stability Index ratings range from 3 (interspaces) to 6 (under plant canopy), but average values should be 4.0 or greater. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Soil data is limited for this site. Soil OM of 6-16% is expected. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Plant community consists of 75-80% grasses, 15% forbs, and 5-10% shrubs. Evenly distributed plant canopy (60-95%) and litter plus moderate infiltration rates result in minimal runoff. Basal cover is typically greater than 10% for this site and does affect runoff on this site. -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
None. -
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:
Mid-size, cool season bunchgrasses>> cool season rhizomatous grasses> perennial forbs>perennial shrubs>tall, cool season bunchgrasses=short, cool season bunchgrasses -
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Minimal decadence, typically associated with shrub component. -
Average percent litter cover (%) and depth ( in):
Litter ranges from 5-40% of total canopy measurement with total litter (including beneath the plant canopy) from 50-90% expected. Herbaceous litter depth typically ranges from 5-15mm. Woody litter can be up to a couple inches (4-6 cm). -
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
English: 1800-2600 lb/ac (2200 lb/ac average); Metric 2016-2912 kg/ha (2464 kg/ha average). -
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:
Bare ground greater than 30% is the most common indicator of a threshold being crossed. Rabbitbrush, Sandberg bluegrass, buckwheat, phlox, and yarrow are common increasers. Kentucky bluegrass, common dandelion, thistles, and annual weeds are common invasive species in disturbed sites. -
Perennial plant reproductive capability:
All species are capable of reproducing, except in extreme drought years.
Print Options
Sections
Font
Other
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.