Natural Resources
Conservation Service
Ecological site R060AY030SD
Porous Clay
Last updated: 6/25/2024
Accessed: 12/31/2024
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.
MLRA notes
Major Land Resource Area (MLRA): 060A–Pierre Shale Plains
The Pierre Shale Plains (MLRA 60A) consists of approximately 10,150 square miles, the majority of which is in South Dakota (70 percent) and small portions are in Montana (2 percent), Nebraska (8 percent), and Wyoming (20 percent). It encircles the Black Hills (MLRA 62) and the Dakota Hogback (MLRA 61). MLRA 60A includes portions of the Oglala, Buffalo Gap, and Thunder Basin National Grasslands. It also includes small sections of the Pine Ridge Indian Reservation, Badlands National Park, and Black Hills National Forest. The Cheyenne and Belle Fourche Rivers flow through the MLRA.
MLRA 60A is in the unglaciated section of the Missouri Plateau, of the Great Plains Province of the Interior Plains. It is an area of old plateaus and terraces that have been deeply eroded. Cretaceous Pierre Shale underlies almost all of this MLRA. This is a marine sediment with layers of volcanic ash that has been altered to smectitic clay. These clays shrink as they dry and swell as they receive moisture. Soils are shallow to very deep and generally are well drained and clayey.
Elevations generally range from 2,620 to 3,610 feet throughout the MLRA, but can range up to 4,260 feet. The average annual precipitation for the western side of the MLRA is 13 to 16 inches, whereas the eastern side receives 16 to 18 inches. A suite of ecological sites has been written specifically for these two precipitation zones. The Locator Map shows the break between the two precipitation zones.
This area supports a mixed natural prairie vegetation consisting of both cool- and warm-season grasses and forbs. Wyoming big sagebrush occurs primarily in the drier western portion of the MLRA, however, small remnant stands can be found in the eastern portion. Dominant land uses of the area are primarily ranching and, to a lesser extent, farming. Major resource concerns to this MLRA are wind erosion and surface water quality.
Classification relationships
USDA - Land Resource Region G – Western Great Plains Range and Irrigated Region, Major Land Resource Area (MLRA) 60A – Pierre Shale Plains.
EPA - Level IV Ecoregions of the Continental United States: 43e – Sagebrush Steppe, 43g Semiarid Pierre Shale Plains, and 43k – Dense Clay Prairie.
Ecological site concept
The Porous Clay ecological site occurs throughout the MLRA. It is located on upland landscapes and does not receive additional moisture from runoff or overflow. Typical slopes range from 2 to 30 percent. Soils are moderately deep to very deep, with a clay, clay loam, or parachannery clay surface texture. The soil is derived from weathered shale and is non-calcareous. Shale chips are found throughout the soil profile (greater than 50 percent by volume) and do not restrict root growth. Because the soil is slightly too strongly acid, areas of bare ground or soft, unconsolidated shale fragments can be present.
The vegetation in reference consists of a mix of cool- and warm-season grasses, however, the mid- to tall- warm-season grasses tend to be the dominant group. Prairie sandreed, little bluestem, prairie cordgrass, and big bluestem are the dominant warm-season grasses. Rhizomatous wheatgrasses are the dominant cool-season grasses. This site functions much like a Sands site.
Associated sites
| R060AY043SD |
Shallow Porous Clay Shallow Porous Clay is a shallow site that is often found adjacent to this site |
|---|
Similar sites
| R060AY043SD |
Shallow Porous Clay Shallow Porous Clay has less production and less prairie sandreed; more tree encroachment; more sun sedge |
|---|
Table 1. Dominant plant species
| Tree |
Not specified |
|---|---|
| Shrub |
(1) Amorpha canescens |
| Herbaceous |
(1) Calamovilfa longifolia |
Physiographic features
This site occurs on gently to moderately rolling uplands.
Table 2. Representative physiographic features
| Landforms |
(1)
Hill
(2) Plain |
|---|---|
| Flooding frequency | None |
| Ponding frequency | None |
| Elevation | 2,500 – 4,300 ft |
| Slope | 2 – 30% |
| Aspect | Aspect is not a significant factor |
Climatic features
The climate in this MLRA is typical of the drier portions of the Northern Great Plains, where sagebrush steppes to the west yield to grassland steppes to the east. Annual precipitation for the entire MLRA ranges from 13 to 18 inches per year, with most occurring during the growing season. 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 masses 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 the more severe occur during late fall, late winter, and spring.
The normal average annual temperature is about 46°F. January is the coldest month with average temperatures ranging from about 19°F (Moorcroft CAA, WY) to about 22°F (Belle Fourche, SD). July is the warmest month with temperatures averaging from about 70°F (Moorcroft CAA, WY) to about 72°F (Belle Fourche, SD). The range of normal average monthly temperatures between the coldest and warmest months is about 51°F. Hourly winds are estimated to average about 11 miles per hour annually, ranging from about 13 miles per hour during the spring to about 10 miles per hour during the summer. Daytime winds generally are stronger than nighttime, and occasional strong storms may bring brief periods of high winds with gusts to more than 50 miles per hour.
Growth of cool-season plants begins in early to mid-March, slowing or ceasing in late June. Warm-season plants begin growth about mid-May and can continue to early or mid-September. Green-up of cool-season plants may occur in September and October when adequate soil moisture is present.
Table 3. Representative climatic features
| Frost-free period (characteristic range) | 98-105 days |
|---|---|
| Freeze-free period (characteristic range) | 123-129 days |
| Precipitation total (characteristic range) | 15-18 in |
| Frost-free period (actual range) | 76-108 days |
| Freeze-free period (actual range) | 113-133 days |
| Precipitation total (actual range) | 14-18 in |
| Frost-free period (average) | 97 days |
| Freeze-free period (average) | 124 days |
| Precipitation total (average) | 16 in |
Figure 2. Monthly precipitation range
Figure 3. Monthly minimum temperature range
Figure 4. Monthly maximum temperature range
Figure 5. Monthly average minimum and maximum temperature
Figure 6. Annual precipitation pattern
Figure 7. Annual average temperature pattern
Climate stations used
-
(1) ARDMORE 1 NW [USC00390236], Edgemont, SD
-
(2) BELLE FOURCHE [USC00390559], Belle Fourche, SD
-
(3) WASTA [USC00398911], Owanka, SD
-
(4) MOORCROFT 3S [USW00024088], Moorcroft, WY
-
(5) REDBIRD [USC00487555], Lance Creek, WY
-
(6) UPTON [USC00489205], Upton, WY
Influencing water features
No significant water features influence this site.
Wetland description
Not Applicable.
Soil features
The soils of this site are parachannery clay loam textured surface soils and slopes of 2 to 30 percent. These soils are moderately deep to very deep, well drained, and have moderately rapid permeability. The soils are formed from acid material weathered from shale and contain many small shale fragments. Sub-surface soil texture is clay. This site should show slight to no evidence of rills. There may be some slight erosion due to wind, and some pedestalling of plants does occur. Water flow paths are broken, irregular in appearance, or discontinuous with numerous debris dams or vegetative barriers. Soil blowing is a severe hazard.
Soils correlated to the Porous Clay ecological site: Maggin, Paiges, Graner
More information can be found in the various soil survey reports. Contact the local USDA Service Center for soil survey reports that include more detail specific to your location.
Table 4. Representative soil features
| Surface texture |
(1) Channery clay loam |
|---|---|
| Family particle size |
(1) Clayey |
| Drainage class | Well drained |
| Permeability class | Moderately rapid |
| Soil depth | 20 – 80 in |
| Surface fragment cover <=3" | 25% |
| Surface fragment cover >3" | Not specified |
| Available water capacity (0-40in) |
2 – 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) |
3.5 – 6 |
| Subsurface fragment volume <=3" (Depth not specified) |
40 – 70% |
| Subsurface fragment volume >3" (Depth not specified) |
Not specified |
Ecological dynamics
This site developed under Northern Great Plains climatic conditions, natural influences of large herbivores, occasional fire, and other biotic and abiotic factors that typically influence soil/site development. Changes will occur in the plant communities due to short-term weather variations, impacts of native and/or exotic plant and animal species, and management actions. While the following plant community descriptions describe more typical transitions between communities that will occur, severe disturbances, such as periods of well-below average precipitation, can cause significant shifts in plant communities and/or species composition.
As this site deteriorates, species such as sedges, forbs, and blue grama will increase. Perennial grasses such as prairie sandreed, little bluestem, big bluestem, and rhizomatous wheatgrass will decrease in frequency and production. Weathered shale dunes may form due to lack of ground cover. The various plant communities on this site are often all contained within a dune-like area under the same grazing management. Soil erosion and dune formation greatly influence the existing plant communities. Depositional areas tend to be dominated by prairie sandreed and bluestem, while the areas from which soil is transported tend to be characterized by sedge, rush, and bare ground. However, the amount of deposition and transport can alter the plant communities. The historic and recent grazing impacts will also influence the plant composition. Prairie sandreed is an important plant to this site. Prairie sandreed has large rhizomes that help hold and bind the soil. As the prairie sandreed decreases along with bluestem and wheatgrass, the hazard for wind erosion increases. Areas can become bare dune-like areas. Where this site occurs adjacent to ponderosa pine woodlands, encroachment of ponderosa pine, bur oak, and juniper may occur.
The plant community upon which interpretations are primarily based is the Reference Plant Community (1.1). The Reference Plant Community has been determined by studying rangeland relic areas, areas protected from excessive disturbance, and areas under long-term rotational grazing regimes. Trends in plant community dynamics ranging from heavily grazed to lightly grazed areas, seasonal use pastures, and historical accounts also have been used. Plant communities, states, transitional pathways, and thresholds have been determined through similar studies and experience.
The following is a diagram that illustrates the common plant communities that can occur on the site and the transition pathways between communities and states. The ecological processes are discussed in more detail in the plant community descriptions following the diagram.
State and transition model
Figure 8. Porous Clay - R060AY030SD
Figure 9. Porous Clay - R060AY030SD
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
Ecosystem states
State 1 submodel, plant communities
State 2 submodel, plant communities
State 1
Reference State
This state represents what is believed to show the natural range of variability that dominated the dynamics in this ecological site prior to European settlement. This site, in reference, is dominated by a mix of warm-season mid- and tall-grasses, and rhizomatous wheatgrasses. Heavy grazing or heavy disturbance, will cause the plant community to transition to a community dominated by the upland sedges and bare ground. Severe erosion is a potential outcome with heavy grazing. In pre-European times the primary disturbances included grazing by large ungulates and small mammals, and drought. Favorable growing conditions occurred during the spring, and warm months of June through August. Today a similar state can be found in areas where proper livestock use has occurred.
Community 1.1
Prairie Sandreed-Little Bluestem-Rhizomatous Wheatgrass
Figure 10. Plant Community Phase 1.1
The plant community upon which interpretations are primarily based is the Prairie Sandreed-Little Bluestem-Rhizomatous Wheatgrass Plant Community (1.1). This is also considered the Reference Plant Community. This plant community is about 75 to 85 percent grasses or grass- likes, 10 to 15 percent forbs, and 5 to 10 percent shrubs by weight. A mix of warm- and cool-season mid-grasses dominates this plant community. Major grasses include prairie sandreed, little bluestem, rhizomatous wheatgrasses, and sand or big bluestem. Other grasses occurring in this plant community include needle and thread, blue grama, sun sedge, threadleaf sedge, and prairie cordgrass. Forbs occurring in this plant community are cudweed sagewort, golden pea, scurfpea, and western yarrow. Significant shrubs include leadplant and rose. Overall this plant community has the appearance of being stable, diverse, and productive. Plant litter is properly distributed with very little movement off-site and natural plant mortality is very low. Most plant species have a wide range of age classes represented and reproduction is not limited. Plant roots occupy most of the soil profile, which provides for soil stability and promotes infiltration. Occasionally this plant community will have areas influenced by natural geologic erosion, and will exhibit characteristics similar to the Sedge/Bare Ground Plant Community Phase (PCP 2.1).
Figure 11. 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 | 685 | 1200 | 1515 |
| Forb | 145 | 188 | 230 |
| Shrub/Vine | 70 | 112 | 155 |
| Total | 900 | 1500 | 1900 |
Figure 12. Plant community growth curve (percent production by month). SD6004, Pierre Shale Plains, warm-season dominant, cool-season sub-dominant. Warm season dominant, cool-season sub-dominant.
| 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 | 3 | 7 | 18 | 25 | 25 | 15 | 7 | 0 | 0 | 0 |
Community 1.2
Rhizomatous Wheatgrass-Blue Grama/Sedge
This plant community develops under moderate, season-long grazing by livestock. The plant community is about 70 to 80 percent grasses or grass-likes, 10 to 20 percent forbs, and 5 to 10 percent shrubs. Dominant grasses include rhizomatous wheatgrasses, blue grama, and sun sedge. Grasses of secondary importance include needle and thread, threadleaf sedge, Junegrass, and Sandberg bluegrass. Prairie sandreed and little bluestem are present in low amounts. Forbs commonly occurring include cudweed sagewort, hairy false goldaster, goldenpea, biscuitroot, wild onion, scarlet globemallow, and pussytoes. Fringed sagewort, plains pricklypear, and fragile cactus can also occur. Leadplant and rose generally have declined in abundance. When compared to the Reference Plant Community (1.1), rhizomatous wheatgrasses and blue grama have increased. Prairie sandreed, sand or big bluestem, and little bluestem have decreased. Rhizomatous wheatgrasses exhibit lower vigor. Non-native annual grasses and forbs may invade the plant community, and bare ground also increases.
Figure 13. Annual production by plant type (representative values) or group (midpoint values)
Table 6. Annual production by plant type
| Plant type | Low (lb/acre) |
Representative value (lb/acre) |
High (lb/acre) |
|---|---|---|---|
| Grass/Grasslike | 475 | 698 | 920 |
| Forb | 85 | 134 | 185 |
| Shrub/Vine | 40 | 68 | 95 |
| Total | 600 | 900 | 1200 |
Figure 14. Plant community growth curve (percent production by month). SD6003, Pierre Shale Plains, cool-season/warm-season co-dominant.. Cool-season, warm-season co-dominant.
| 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 | 3 | 10 | 20 | 28 | 21 | 10 | 5 | 3 | 0 | 0 |
Pathway 1.1A
Community 1.1 to 1.2
Continuous season-long grazing will convert this plant community to the Rhizomatous Wheatgrass-Blue Grama/Sedge Plant Community (1.2). Heavy continuous seasonal grazing will also cause this shift to occur.
Pathway 1.2A
Community 1.2 to 1.1
Prescribed grazing, including proper stocking rates, change in season of use, and adequate recovery, will convert this plant community to the Prairie Sandreed/Little Bluestem Plant Community.
State 2
Disturbed State
Typically this plant community is the result of frequent and severe grazing, or heavy disturbance, and erosion. This plant community is also found in areas that exhibit increased bare ground due to natural geologic erosion. These areas often occur adjacent to shale outcrops, or in association with the Shallow Porous Clay ecological site. Short grass and grass-like plants such as sun sedge, prairie Junegrass, Dudley’s rush, and bluegrass dominate this plant community. Annual grasses such as cheatgrass and annual forbs such as mustards may be common. Fragile cactus and plains pricklypear may also occur. The plant community is about 75 to 85 percent grass and grass-likes, 10 to 15 percent forbs, and 1 to 5 percent shrubs. When compared to the Reference Plant Community (1.1) the perennial tall- and mid-grasses have greatly decreased. Short grasses and sedges dominate the plant community. The dominant forbs are cudweed sagewort, mustards, yarrow, pussytoes, cactus, and golden pea. Bare ground has greatly increased, and large areas of no vegetation may be present.
Community 2.1
Sedge/Bare Ground
Typically this plant community is the result of frequent and severe grazing, or heavy disturbance, and erosion. This plant community is also found in areas that exhibit increased bare ground due to natural geologic erosion. These areas often occur adjacent to shale outcrops, or in association with the Shallow Porous Clay ecological site. Short grass and grass-like plants such as sun sedge, prairie Junegrass, Dudley’s rush, and bluegrass dominate this plant community. Annual grasses such as annual brome and annual forbs such as mustards may be common. Fragile cactus and plains pricklypear may also occur. The plant community is about 75 to 85 percent grass and grass-likes, 10 to 15 percent forbs, and 1 to 5 percent shrubs. When compared to the Reference Plant Community (1.1) the perennial tall- and mid-grasses have greatly decreased. Short grasses and sedges dominate the plant community. The dominant forbs are cudweed sagewort, mustards, yarrow, pussytoes, cactus and golden pea. Bare ground has greatly increased, and large areas of no vegetation may be present.
Figure 15. Annual production by plant type (representative values) or group (midpoint values)
Table 7. Annual production by plant type
| Plant type | Low (lb/acre) |
Representative value (lb/acre) |
High (lb/acre) |
|---|---|---|---|
| Grass/Grasslike | 75 | 254 | 430 |
| Forb | 25 | 38 | 50 |
| Shrub/Vine | 0 | 8 | 20 |
| Total | 100 | 300 | 500 |
Figure 16. Plant community growth curve (percent production by month). SD6001, Pierre Shale Plains, cool-season dominant. Cool-season dominant..
| 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 | 4 | 12 | 25 | 36 | 10 | 5 | 4 | 4 | 0 | 0 |
Transition T1A
State 1 to 2
Frequent and severe grazing, or heavy disturbance, and soil surface erosion will convert this plant community to the Sedge/Bare Ground Plant Community (2.1).
Restoration pathway R2A
State 2 to 1
Removal of management-induced disturbances, in combination with long-term prescribed grazing, which may include extended periods of non-use, may convert this PCP to the Rhizomatous Wheatgrass-Blue Grama Plant Community (1.2). This transition may not be fast and/or feasible.
Additional community tables
Table 8. Community 1.1 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 1 | Prairie Sandreed | 300–450 | ||||
| prairie sandreed | CALO | Calamovilfa longifolia | 300–450 | – | ||
| 2 | Little Bluestem | 300–450 | ||||
| little bluestem | SCSC | Schizachyrium scoparium | 300–450 | – | ||
| 3 | Rhizomatous Wheatgrasses | 75–225 | ||||
| thickspike wheatgrass | ELLAL | Elymus lanceolatus ssp. lanceolatus | 75–225 | – | ||
| western wheatgrass | PASM | Pascopyrum smithii | 75–225 | – | ||
| 4 | Warm-Season Grasses | 75–375 | ||||
| big bluestem | ANGE | Andropogon gerardii | 75–225 | – | ||
| sand bluestem | ANHA | Andropogon hallii | 75–225 | – | ||
| sideoats grama | BOCU | Bouteloua curtipendula | 0–150 | – | ||
| switchgrass | PAVI2 | Panicum virgatum | 0–150 | – | ||
| prairie cordgrass | SPPE | Spartina pectinata | 0–75 | – | ||
| 5 | Native Grasses and Grass-likes | 75–225 | ||||
| Grass, perennial | 2GP | Grass, perennial | 0–75 | – | ||
| blue grama | BOGR2 | Bouteloua gracilis | 0–75 | – | ||
| needleleaf sedge | CADU6 | Carex duriuscula | 0–75 | – | ||
| threadleaf sedge | CAFI | Carex filifolia | 0–75 | – | ||
| sun sedge | CAINH2 | Carex inops ssp. heliophila | 15–75 | – | ||
| plains reedgrass | CAMO | Calamagrostis montanensis | 0–75 | – | ||
| needle and thread | HECOC8 | Hesperostipa comata ssp. comata | 0–75 | – | ||
| Dudley's rush | JUDU2 | Juncus dudleyi | 15–75 | – | ||
| prairie Junegrass | KOMA | Koeleria macrantha | 15–75 | – | ||
| Sandberg bluegrass | POSE | Poa secunda | 15–75 | – | ||
| threeawn | ARIST | Aristida | 0 | – | ||
|
Forb
|
||||||
| 7 | Forbs | 150–225 | ||||
| large Indian breadroot | PEES | Pediomelum esculentum | 0–45 | – | ||
| upright prairie coneflower | RACO3 | Ratibida columnifera | 0–45 | – | ||
| Missouri goldenrod | SOMI2 | Solidago missouriensis | 0–45 | – | ||
| prairie thermopsis | THRH | Thermopsis rhombifolia | 15–45 | – | ||
| American vetch | VIAM | Vicia americana | 0–45 | – | ||
| Forb, perennial | 2FP | Forb, perennial | 0–45 | – | ||
| white sagebrush | ARLU | Artemisia ludoviciana | 15–45 | – | ||
| aster | ASTER | Aster | 0–45 | – | ||
| tapertip hawksbeard | CRAC2 | Crepis acuminata | 0–45 | – | ||
| white prairie clover | DACA7 | Dalea candida | 0–45 | – | ||
| purple prairie clover | DAPU5 | Dalea purpurea | 0–45 | – | ||
| hairy false goldenaster | HEVI4 | Heterotheca villosa | 0–45 | – | ||
| desertparsley | LOMAT | Lomatium | 0–45 | – | ||
| bluebells | MERTE | Mertensia | 15–45 | – | ||
| dotted blazing star | LIPU | Liatris punctata | 0–30 | – | ||
| alpine golden buckwheat | ERFLF | Eriogonum flavum var. flavum | 0–30 | – | ||
| milkvetch | ASTRA | Astragalus | 15–30 | – | ||
| common yarrow | ACMI2 | Achillea millefolium | 0–30 | – | ||
| stemless four-nerve daisy | TEAC | Tetraneuris acaulis | 0–30 | – | ||
| onion | ALLIU | Allium | 0–15 | – | ||
| field pussytoes | ANNE | Antennaria neglecta | 0–15 | – | ||
| rosy pussytoes | ANRO2 | Antennaria rosea | 0–15 | – | ||
| scarlet beeblossom | OESU3 | Oenothera suffrutescens | 0–15 | – | ||
| curlycup gumweed | GRSQ | Grindelia squarrosa | 0 | – | ||
| thistle | CIRSI | Cirsium | 0 | – | ||
| Forb, annual | 2FA | Forb, annual | 0 | – | ||
| goatsbeard | TRAGO | Tragopogon | 0 | – | ||
|
Shrub/Vine
|
||||||
| 8 | Shrubs | 75–150 | ||||
| leadplant | AMCA6 | Amorpha canescens | 15–45 | – | ||
| skunkbush sumac | RHTR | Rhus trilobata | 0–45 | – | ||
| rose | ROSA5 | Rosa | 0–45 | – | ||
| soapweed yucca | YUGL | Yucca glauca | 0–30 | – | ||
| Shrub (>.5m) | 2SHRUB | Shrub (>.5m) | 0–30 | – | ||
Table 9. Community 1.2 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 1 | Prairie Sandreed | 0–45 | ||||
| prairie sandreed | CALO | Calamovilfa longifolia | 0–45 | – | ||
| 2 | Little Bluestem | 0–90 | ||||
| little bluestem | SCSC | Schizachyrium scoparium | 0–90 | – | ||
| 3 | Rhizomatous Wheatgrasses | 180–360 | ||||
| western wheatgrass | PASM | Pascopyrum smithii | 90–315 | – | ||
| thickspike wheatgrass | ELLAL | Elymus lanceolatus ssp. lanceolatus | 90–180 | – | ||
| 4 | Warm-Season Grasses | 18–90 | ||||
| sideoats grama | BOCU | Bouteloua curtipendula | 0–45 | – | ||
| switchgrass | PAVI2 | Panicum virgatum | 0–45 | – | ||
| big bluestem | ANGE | Andropogon gerardii | 0–27 | – | ||
| sand bluestem | ANHA | Andropogon hallii | 0–27 | – | ||
| prairie cordgrass | SPPE | Spartina pectinata | 0 | – | ||
| 5 | Native Grasses and Grass-likes | 135–360 | ||||
| blue grama | BOGR2 | Bouteloua gracilis | 90–225 | – | ||
| needleleaf sedge | CADU6 | Carex duriuscula | 18–90 | – | ||
| threadleaf sedge | CAFI | Carex filifolia | 18–90 | – | ||
| sun sedge | CAINH2 | Carex inops ssp. heliophila | 45–90 | – | ||
| Dudley's rush | JUDU2 | Juncus dudleyi | 18–72 | – | ||
| prairie Junegrass | KOMA | Koeleria macrantha | 9–45 | – | ||
| Sandberg bluegrass | POSE | Poa secunda | 9–45 | – | ||
| needle and thread | HECOC8 | Hesperostipa comata ssp. comata | 0–45 | – | ||
| plains reedgrass | CAMO | Calamagrostis montanensis | 0–27 | – | ||
| threeawn | ARIST | Aristida | 0–27 | – | ||
| Grass, perennial | 2GP | Grass, perennial | 0–18 | – | ||
| 6 | Non-native Grasses | 0–45 | ||||
| cheatgrass | BRTE | Bromus tectorum | 0–45 | – | ||
| Kentucky bluegrass | POPR | Poa pratensis | 0–45 | – | ||
|
Forb
|
||||||
| 7 | Forbs | 90–180 | ||||
| prairie thermopsis | THRH | Thermopsis rhombifolia | 9–36 | – | ||
| Forb, annual | 2FA | Forb, annual | 0–36 | – | ||
| white sagebrush | ARLU | Artemisia ludoviciana | 9–36 | – | ||
| aster | ASTER | Aster | 0–27 | – | ||
| thistle | CIRSI | Cirsium | 0–27 | – | ||
| Forb, perennial | 2FP | Forb, perennial | 0–27 | – | ||
| common yarrow | ACMI2 | Achillea millefolium | 9–27 | – | ||
| curlycup gumweed | GRSQ | Grindelia squarrosa | 0–27 | – | ||
| upright prairie coneflower | RACO3 | Ratibida columnifera | 0–27 | – | ||
| Missouri goldenrod | SOMI2 | Solidago missouriensis | 0–27 | – | ||
| goatsbeard | TRAGO | Tragopogon | 0–27 | – | ||
| stemless four-nerve daisy | TEAC | Tetraneuris acaulis | 0–18 | – | ||
| purple prairie clover | DAPU5 | Dalea purpurea | 0–18 | – | ||
| alpine golden buckwheat | ERFLF | Eriogonum flavum var. flavum | 0–18 | – | ||
| hairy false goldenaster | HEVI4 | Heterotheca villosa | 0–18 | – | ||
| dotted blazing star | LIPU | Liatris punctata | 0–18 | – | ||
| desertparsley | LOMAT | Lomatium | 0–18 | – | ||
| bluebells | MERTE | Mertensia | 0–18 | – | ||
| onion | ALLIU | Allium | 0–18 | – | ||
| field pussytoes | ANNE | Antennaria neglecta | 0–18 | – | ||
| rosy pussytoes | ANRO2 | Antennaria rosea | 0–18 | – | ||
| milkvetch | ASTRA | Astragalus | 9–18 | – | ||
| white prairie clover | DACA7 | Dalea candida | 0–9 | – | ||
| American vetch | VIAM | Vicia americana | 0 | – | ||
| tapertip hawksbeard | CRAC2 | Crepis acuminata | 0 | – | ||
| scarlet beeblossom | OESU3 | Oenothera suffrutescens | 0 | – | ||
| large Indian breadroot | PEES | Pediomelum esculentum | 0 | – | ||
|
Shrub/Vine
|
||||||
| 8 | Shrubs | 45–90 | ||||
| soapweed yucca | YUGL | Yucca glauca | 0–36 | – | ||
| skunkbush sumac | RHTR | Rhus trilobata | 0–27 | – | ||
| rose | ROSA5 | Rosa | 0–27 | – | ||
| Shrub (>.5m) | 2SHRUB | Shrub (>.5m) | 0–27 | – | ||
| leadplant | AMCA6 | Amorpha canescens | 0 | – | ||
Table 10. Community 2.1 plant community composition
| Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
|---|---|---|---|---|---|---|
|
Grass/Grasslike
|
||||||
| 2 | Little Bluestem | 0–15 | ||||
| little bluestem | SCSC | Schizachyrium scoparium | 0–15 | – | ||
| 3 | Rhizomatous Wheatgrasses | 0–30 | ||||
| western wheatgrass | PASM | Pascopyrum smithii | 0–30 | – | ||
| thickspike wheatgrass | ELLAL | Elymus lanceolatus ssp. lanceolatus | 0–15 | – | ||
| 4 | Warm-Season Grasses | 0–9 | ||||
| sideoats grama | BOCU | Bouteloua curtipendula | 0–9 | – | ||
| switchgrass | PAVI2 | Panicum virgatum | 0 | – | ||
| prairie cordgrass | SPPE | Spartina pectinata | 0 | – | ||
| big bluestem | ANGE | Andropogon gerardii | 0 | – | ||
| sand bluestem | ANHA | Andropogon hallii | 0 | – | ||
| 5 | Native Grasses and Grass-likes | 90–180 | ||||
| sun sedge | CAINH2 | Carex inops ssp. heliophila | 15–60 | – | ||
| needleleaf sedge | CADU6 | Carex duriuscula | 15–45 | – | ||
| threadleaf sedge | CAFI | Carex filifolia | 15–45 | – | ||
| Dudley's rush | JUDU2 | Juncus dudleyi | 9–30 | – | ||
| blue grama | BOGR2 | Bouteloua gracilis | 0–30 | – | ||
| Sandberg bluegrass | POSE | Poa secunda | 6–24 | – | ||
| prairie Junegrass | KOMA | Koeleria macrantha | 3–15 | – | ||
| needle and thread | HECOC8 | Hesperostipa comata ssp. comata | 0–15 | – | ||
| threeawn | ARIST | Aristida | 0–15 | – | ||
| Grass, perennial | 2GP | Grass, perennial | 0–6 | – | ||
| plains reedgrass | CAMO | Calamagrostis montanensis | 0 | – | ||
| 6 | Non-native Grasses | 0–30 | ||||
| cheatgrass | BRTE | Bromus tectorum | 0–24 | – | ||
| Kentucky bluegrass | POPR | Poa pratensis | 0–9 | – | ||
|
Forb
|
||||||
| 7 | Forbs | 30–45 | ||||
| goatsbeard | TRAGO | Tragopogon | 0–15 | – | ||
| Forb, annual | 2FA | Forb, annual | 0–15 | – | ||
| Forb, perennial | 2FP | Forb, perennial | 0–15 | – | ||
| white sagebrush | ARLU | Artemisia ludoviciana | 3–15 | – | ||
| thistle | CIRSI | Cirsium | 0–15 | – | ||
| curlycup gumweed | GRSQ | Grindelia squarrosa | 0–15 | – | ||
| common yarrow | ACMI2 | Achillea millefolium | 0–12 | – | ||
| prairie thermopsis | THRH | Thermopsis rhombifolia | 3–12 | – | ||
| Missouri goldenrod | SOMI2 | Solidago missouriensis | 0–9 | – | ||
| aster | ASTER | Aster | 0–9 | – | ||
| alpine golden buckwheat | ERFLF | Eriogonum flavum var. flavum | 0–9 | – | ||
| purple prairie clover | DAPU5 | Dalea purpurea | 0–6 | – | ||
| dotted blazing star | LIPU | Liatris punctata | 0–6 | – | ||
| milkvetch | ASTRA | Astragalus | 3–6 | – | ||
| stemless four-nerve daisy | TEAC | Tetraneuris acaulis | 0–6 | – | ||
| upright prairie coneflower | RACO3 | Ratibida columnifera | 0–6 | – | ||
| onion | ALLIU | Allium | 0–3 | – | ||
| field pussytoes | ANNE | Antennaria neglecta | 0–3 | – | ||
| rosy pussytoes | ANRO2 | Antennaria rosea | 0–3 | – | ||
| tapertip hawksbeard | CRAC2 | Crepis acuminata | 0 | – | ||
| white prairie clover | DACA7 | Dalea candida | 0 | – | ||
| desertparsley | LOMAT | Lomatium | 0 | – | ||
| bluebells | MERTE | Mertensia | 0 | – | ||
| scarlet beeblossom | OESU3 | Oenothera suffrutescens | 0 | – | ||
| large Indian breadroot | PEES | Pediomelum esculentum | 0 | – | ||
| hairy false goldenaster | HEVI4 | Heterotheca villosa | 0 | – | ||
| American vetch | VIAM | Vicia americana | 0 | – | ||
|
Shrub/Vine
|
||||||
| 8 | Shrubs | 3–15 | ||||
| skunkbush sumac | RHTR | Rhus trilobata | 0–9 | – | ||
| rose | ROSA5 | Rosa | 0–9 | – | ||
| soapweed yucca | YUGL | Yucca glauca | 0–6 | – | ||
| Shrub (>.5m) | 2SHRUB | Shrub (>.5m) | 0–6 | – | ||
| leadplant | AMCA6 | Amorpha canescens | 0 | – | ||
Interpretations
Animal community
The following table lists annual suggested initial stocking rates with average growing conditions. These are conservative estimates that should be used only as guidelines in the initial stages of conservation planning. Often, the current plant composition does not entirely match any particular plant community (as described in this Ecological Site Description). Therefore, a resource inventory is necessary to document plant composition and production. More accurate carrying capacity estimates should eventually be calculated using the following stocking rate information along with animal preference data and actual stocking records, particularly when grazers other than cattle are involved. With consultation of the land manager, more intensive grazing management may result in improved harvest efficiencies and increased carrying capacity.
Plant Community = Prairie Sandreed-Little Bluestem-Rhizomatous Wheatgrass (1.1)
Average Annual Production (lbs./ac, air-dry) = 1500
Stocking Rate (AUM/ac) = 0.41
Plant Community = Rhizomatous Wheatgrass-Blue Grama/Sedge (1.2)
Average Annual Production (lbs./ac, air-dry) = 900
Stocking Rate (AUM/ac) = 0.25
Plant Community = Sedge/Bare Ground (2.1)
Average Annual Production (lbs./ac, air-dry) = 300
Stocking Rate (AUM/ac) = 0.08
*Based on 912 lbs./acre (air-dry weight) per Animal Unit Month (AUM), and on 25 percent harvest efficiency of preferred and desirable forage species (refer to USDA NRCS, National Range and Pasture Handbook).
Total annual production on-site may contain vegetation deemed undesirable or untargeted by the grazing animal. Therefore, AUM values may have been reduced to reflect only preferred or desirable forage species.
Grazing by domestic livestock is one of the major income-producing industries in the area. Rangeland in this area may provide yearlong forage. During the dormant period, the forage for livestock will likely be lacking protein to meet livestock requirements, and added protein will allow ruminants to better utilize the energy stored in grazed plant materials. A forage quality test (either directly or through fecal sampling) should be used to determine the level of supplementation needed.
Hydrological functions
Water is the principal factor limiting forage production on this site. This site is dominated by soils in hydrologic group B. Infiltration ranges from high to very high. Runoff potential for this site varies from medium to very high depending on slope and ground cover. In many cases, areas with greater than 75 percent 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. Normally areas where ground cover is less than 50 percent have the greatest potential to have reduced infiltration and higher runoff (refer to Section 4, NRCS National Engineering Handbook for runoff quantities and hydrologic curves).
Recreational uses
This site provides hunting opportunities for upland game species. The wide variety of plants which bloom from spring until fall have an aesthetic value that appeals to visitors.
Other products
Seed harvest of native plant species can provide additional income on this site.
Other information
Revision Notes: “Previously Approved” Provisional
This Provisional ecological site concept has passed Quality Control (QC) and Quality Assurance (QA) to ensure that the site meets the 2014 NESH standards for a Provisional ecological site. This is an updated “Previously Approved” ESD which represents a first-generation tier of documentation that, prior to the release of the 2014 National Ecological Site Handbook (NESH), met all requirements as an “Approved” ESD as laid out in the 1997, rev.1, 2003 National Range and Pasture Handbook (NRPH). The document fully described the Reference State and Community Phase in the State-and-Transition model. All other alternative states are at least described in narrative form. The “Previously Approved” ESD has been field-tested for a minimum of five years and is a proven functional document for conservation planning. The “Previously Approved” ESD does not contain all tabular and narrative entries as required in the current “Approved” level of documentation but it is expected that the “Previously Approved” ESD will continue refinement towards an “Approved” status.
Site Development and Testing Plan:
Future work, as described in a Project Plan, is needed to validate the information in this Provisional Ecological Site Description. This will include field activities to collect low-, medium-, and high-intensity sampling, soil correlations, and analysis of that data. Annual field reviews should be done by soil scientists and vegetation specialists. The final field review, peer review, quality control, and quality assurance reviews of the ESD will be needed to produce the final document.
Non-discrimination Statement
In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA programs are prohibited from discriminating based on race, color, national origin, religion, sex, gender identity (including gender expression), sexual orientation, disability, age, marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines vary by program or incident.
Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American Sign Language, etc.) should contact the responsible Agency or USDA's TARGET Center at (202) 720-2600 (voice and TTY) or contact USDA through the Federal Relay Service at (800) 877-8339. Additionally, program information may be made available in languages other than English.
To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, available online and at any USDA office, or write a letter addressed to USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call (866) 632- 9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410; (2) fax: (202) 690-7442; or (3) email: program.intake@usda.gov.
Supporting information
Inventory data references
Information presented here has been derived from NRCS clipping data and other inventory data. Field observations from range trained personnel was also used. Those involved in developing this site description include: Everet Bainter, Range Management Specialist, NRCS; Stan Boltz, Range Management Specialist, NRCS; Glen Mitchell, Range Management Specialist, NRCS; Cheryl Nielsen, Range Management Specialist, NRCS.
Data Source Number of Records Sample Period State County
SCS-RANGE-417 3 1985 – 1986 WY Weston
Other references
EPA – Level III and Level IV Ecoregions of the Continental United States, (https://www.epa.gov/eco-research/level-iii-and-iv-ecoregions- continental-united-states). Available online. Accessed 01/03/17
High Plains Regional Climate Center, University of Nebraska, (http://www.hprcc.unl.edu/). Available online. Accessed 02/27/17.
USDA, NRCS. Soil Survey Staff. Official Soil Series Descriptions. Available online. Accessed 04/23/17.
USDA, NRCS. Soil Survey Staff. Web Soil Survey. Available online. Accessed 04/23/17.
USDA, NRCS. 2006. Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin. Ag Handbook 296.
USDA, NRCS. 2014. National Ecological Site Handbook, 1st Ed.
USDA, NRCS. National Water and Climate Center. (http://www.wcc.nrcs.usda.gov/). Available online. Accessed 02/27/17.
USDA, NRCS. 1997, rev. 1, 2003. National Range and Pasture Handbook.
USDA, NRCS. National Soil Information System, Information Technology Center. (http://nasis.nrcs.usda.gov).
USDA, NRCS. 2017. The PLANTS Database (http://plants.usda.gov, 2017). Available online. Accessed 4/3/17.
USDA, NRCS. Various Published Soil Surveys.
Contributors
Stan Boltz
Approval
Suzanne Mayne-Kinney, 6/25/2024
Acknowledgments
ESD updated by Rick L. Peterson, 4/24/17
MLRA 60A Provisional Level Quality Control (QC) Process 9/28/17
Ecological Site from MLRA 60A were Previously Approved ESDs and meet the requirements as stated in the 2003 National Range and Pasture Handbook.
The Sites were updated to the Provisional Level by Rick L. Peterson, ESS, Rapid City, SSO in FY17.
The sites were reviewed by George Gamblin, RMS, Wheatland, WY and Mitch Faulkner, RMS, Belle Fourche, SD. Mitch Faulkner acted as the Provisional QC. The Sites were then reviewed and approved at the Provisional Level by David Kraft, Regional ESS, Salina, KS.
Worked closely with Kent Cooley, Area SS, with MLRA key development and soils narratives
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) | Stan Boltz |
|---|---|
| Contact for lead author | stanley.boltz@sd.usda.gov, 605-352-1236 |
| Date | 11/30/2012 |
| Approved by | Suzanne Mayne-Kinney |
| Approval date | |
| Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
None. Occasional small areas of exposed shale may occur in association with this site, and may exhibit rills, but these areas are not considered part of this site. -
Presence of water flow patterns:
None, or barely visible and discontinuous. -
Number and height of erosional pedestals or terracettes:
Some pedestalling of plants occurs on steeper slopes, but no evidence of recent erosion (exposed roots) should be present. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
5 to 15 percent is typical. Occasional small areas of exposed shale may occur in association with this site, but these areas are not considered part of this site. -
Number of gullies and erosion associated with gullies:
None should be present. -
Extent of wind scoured, blowouts and/or depositional areas:
None. -
Amount of litter movement (describe size and distance expected to travel):
Slight amount of movement of smallest size class litter is possible, but not normal. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil aggregate stability ratings should typically be 5 to 6, normally 6. Surface organic matter adheres to the soil surface. Soil surface fragments will typically retain structure indefinitely when dipped in distilled water. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
A-horizon should be 5 to 7 inches thick with mollic (dark) colors when moist. Structure typically is medium to coarse granular at least in the upper A-horizon. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Combination of shallow and deep rooted species (mid & tall rhizomatous and tufted perennial cool-season grasses) with fine and coarse roots positively influences infiltration. -
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:
Tall warm-season rhizomatous grasses > mid warm-season grasses >Sub-dominant:
Mid cool-season rhizomatous grasses > forbs >Other:
Short grass-likes > cool-season rhizomatous grasses = shrubsAdditional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Very little evidence of decadence or mortality. Bunch grasses have strong, healthy centers and shrubs are vigorous. -
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Production ranges from 900-1,900 lbs./acre (air-dry weight). Reference value production is 1,500 lbs./acre (air-dry weight). -
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:
State and local noxious weeds, Kentucky bluegrass, annual bromes. -
Perennial plant reproductive capability:
Perennial grasses should have vigorous rhizomes or tillers.
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