Natural Resources
Conservation Service
Ecological site R064XY045NE
Dense Clay
Accessed: 05/11/2024
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.
Classification relationships
Level IV Ecoregions of the Conterminous United States: 25a – Pine Ridge Escarpment, 43h – White River Badlands, and 43i – Keya Paha Tablelands.
Associated sites
R064XY014NE |
Clayey 14-17" PZ |
---|---|
R064XY035NE |
Clayey 17-20 PZ |
R064XY044NE |
Claypan |
R064XY046NE |
Thin Claypan |
Similar sites
R064XY035NE |
Clayey 17-20 PZ [More green needlegrass; higher production.] |
---|---|
R064XY014NE |
Clayey 14-17" PZ [More green needlegrass; higher production.] |
R064XY046NE |
Thin Claypan [Lower production; greater dominance of short grass and salt tolerant species.] |
Table 1. Dominant plant species
Tree |
Not specified |
---|---|
Shrub |
Not specified |
Herbaceous |
(1) Pascopyrum smithii |
Physiographic features
This site occurs on nearly level to sloping upland valleys, fans and stream terraces.
Table 2. Representative physiographic features
Landforms |
(1)
Stream terrace
(2) Alluvial fan (3) Plain |
---|---|
Flooding frequency | None |
Ponding frequency | None |
Elevation | 2,900 – 4,000 ft |
Slope | 15% |
Aspect | Aspect is not a significant factor |
Climatic features
MLRA 64 is considered to have a continental climate – cold winters and hot summers, low humidity, light rainfall, and much sunshine. Extremes in temperature may also abound. The climate is the result of this MLRA’s location near the geographic center of North America. There are few natural barriers on the northern Great Plains and air masses move freely across the plains and account for rapid changes in temperature.
Annual precipitation ranges from 14 to 20 inches per year. The normal average annual temperature is about 47° F. January is the coldest month with average temperatures ranging from about 21° F (Wood, SD) to about 25° F (Hemingford, NE). July is the warmest month with temperatures averaging from about 70° F (Keeline 3 W, WY) to about 76° F (Wood, SD). The range of normal average monthly temperatures between the coldest and warmest months is about 55° F. This large annual range attests to the continental nature of this area's climate. Hourly winds 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 are generally 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 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 (average) | 143 days |
---|---|
Freeze-free period (average) | 163 days |
Precipitation total (average) | 20 in |
Figure 2. Monthly precipitation range
Figure 3. Monthly average minimum and maximum temperature
Influencing water features
No riparian areas or wetland features are directly associated with this site.
Soil features
The common features of soils in this site are the clay textured soils and slopes of 0 to 15 percent. The soils in this site are moderately well to well drained and formed in clayey alluvium or residuum from soft shale. The clay surface layer is 1 to 5 inches thick. The soils have a slow to very slow infiltration rate except after dry periods when initial uptake may be rapid due to cracking of the surface. Gilgai microrelief occurs in most areas. When dry these soils crack. Wet surface compaction can occur with heavy traffic. This site typically should show slight to no evidence of rills, wind scoured areas or pedestalled plants. Water flow paths are broken, irregular in appearance or discontinuous with numerous debris dams or vegetative barriers. The soil surface is stable and intact. Sub-surface soil layers are moderately restrictive to water movement and root penetration.
These soils are susceptible to wind and water erosion. The hazard of water erosion increases on slopes greater than about 6 percent.
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) Clay |
---|---|
Family particle size |
(1) Clayey |
Drainage class | Moderately well drained to well drained |
Permeability class | Very slow |
Soil depth | 20 – 80 in |
Surface fragment cover <=3" | Not specified |
Surface fragment cover >3" | Not specified |
Available water capacity (0-40in) |
2 – 4 in |
Calcium carbonate equivalent (0-40in) |
15% |
Electrical conductivity (0-40in) |
16 mmhos/cm |
Sodium adsorption ratio (0-40in) |
25 |
Soil reaction (1:1 water) (0-40in) |
5.6 – 9 |
Subsurface fragment volume <=3" (Depth not specified) |
Not specified |
Subsurface fragment volume >3" (Depth not specified) |
Not specified |
Ecological dynamics
This site developed under Northern Great Plains climatic conditions, light to severe grazing by bison and other large herbivores, sporadic natural or man-caused wildfire (often of light intensities), 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.
These soils are high in clay and have a low available water capacity. The shrink-swell potential is very high, resulting in cracks greater than 2 inches wide during dry periods. Western wheatgrass with its strong rhizomes and high drought tolerance is able to thrive in these soils. Western wheatgrass dominates the site and production is closely related to the vigor of western wheatgrass. Slickspots are sometimes associated with this site. Slickspots are bare ground areas that are affected by high sodium concentrations. The soil factors are the dominant influence and grazing management does not typically affect these areas.
Interpretations are primarily based on the Western Wheatgrass Plant Community. It has been determined by study of 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 diagram illustrates the common plant communities and vegetation states commonly occurring on the site and the transition pathways between communities and states. The ecological processes will be discussed in more detail in the plant community descriptions 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
Ecosystem states
State 1 submodel, plant communities
State 2 submodel, plant communities
State 1
Western Wheatgrass
Community 1.1
Western Wheatgrass
Interpretations are based primarily on the Western Wheatgrass Plant Community (this is also considered to be climax). This plant community evolved with grazing by large herbivores and occasional fire, and can be maintained with prescribed grazing, prescribed burning, or areas receiving occasional short periods of rest. The potential vegetation is about 85% grasses or grass-like plants, 10% forbs, and 5% shrubs. Cool season grasses dominate the plant community. The major grasses include western wheatgrass and green needlegrass. The plant diversity is low. Other grasses and grass-like species occurring may include Sandberg bluegrass, buffalograss, blue grama, sideoats grama and sedge. The dominant forbs include biscuitroot, wild parsley, scarlet globemallow, and American vetch. Shrubs that may occur on the plant community include brittle cactus and plains pricklypear. This plant community is resilient and well adapted to the Northern Great Plains climatic conditions. However two to three years of drought can greatly reduce the vigor and abundance of the green needlegrass and western wheatgrass, increasing the percent bare ground and creating moderate to high soil erosion potential. The actual plant composition may not be greatly changed, however the production of this plant community varies greatly with fluctuations in precipitation. Water infiltration is low and runoff is moderate to high because of the high clay content in the soil. Plant litter is properly distributed with some movement off-site and natural plant mortality is low.
Figure 4. Annual production by plant type (representative values) or group (midpoint values)
Table 5. Annual production by plant type
Plant type | Low (lb/acre) |
Representative value (lb/acre) |
High (lb/acre) |
---|---|---|---|
Grass/Grasslike | 900 | 1402 | 1795 |
Forb | 0 | 75 | 155 |
Shrub/Vine | 0 | 23 | 50 |
Total | 900 | 1500 | 2000 |
Figure 5. Plant community growth curve (percent production by month). NE6401, Pine Ridge/Badlands, 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 |
5 | 15 | 28 | 30 | 10 | 2 | 5 | 5 |
State 2
Western Wheatgrass, Bare Ground
Community 2.1
Western Wheatgrass, Bare Ground
This plant community develops under droughty conditions or heavy continuous grazing. The potential vegetation is made up of 90% grasses & grass-likes, 5% forbs and 5% shrubs. The grass component is almost entirely western wheatgrass. Other perennial grasses are generally not found. Forbs found in this plant community include pennycress, curlycup gumweed, sweetclover and annual forbs. Shrubs found include brittle cactus and plains pricklypear. When compared to the Western Wheatgrass Plant Community, the vigor, production and basal density of the grasses has been reduced. Often the site will be bare ground with a few sprigs of western wheatgrass, and cheatgrass will likely invade this plant community. The plant diversity is extremely low. Due to the low basal density, soil erosion hazards are high. Moving this plant community toward the Western Wheatgrass Plant Community can be accomplished through prescribed grazing and favorable climatic conditions.
Figure 6. 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 | 500 | 760 | 910 |
Shrub/Vine | 0 | 20 | 45 |
Forb | 0 | 20 | 45 |
Total | 500 | 800 | 1000 |
Figure 7. Plant community growth curve (percent production by month). NE6401, Pine Ridge/Badlands, 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 |
5 | 15 | 28 | 30 | 10 | 2 | 5 | 5 |
Additional community tables
Table 7. Community 1.1 plant community composition
Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
---|---|---|---|---|---|---|
Grass/Grasslike
|
||||||
1 | Western Wheatgrass | 600–900 | ||||
western wheatgrass | PASM | Pascopyrum smithii | 600–900 | – | ||
2 | Warm-Season Grasses | 0–150 | ||||
sideoats grama | BOCU | Bouteloua curtipendula | 0–75 | – | ||
blue grama | BOGR2 | Bouteloua gracilis | 0–75 | – | ||
3 | Needlegrasses | 300–600 | ||||
green needlegrass | NAVI4 | Nassella viridula | 300–600 | – | ||
4 | Native Grasses and Grass-likes | 0–75 | ||||
Grass, perennial | 2GP | Grass, perennial | 0–75 | – | ||
sedge | CAREX | Carex | 0–75 | – | ||
prairie Junegrass | KOMA | Koeleria macrantha | 0–75 | – | ||
Sandberg bluegrass | POSE | Poa secunda | 0–75 | – | ||
Forb
|
||||||
6 | Forbs | 0–150 | ||||
American vetch | VIAM | Vicia americana | 0–75 | – | ||
leafy wildparsley | MUDI | Musineon divaricatum | 0–75 | – | ||
desert biscuitroot | LOFO | Lomatium foeniculaceum | 0–75 | – | ||
American bird's-foot trefoil | LOUNU | Lotus unifoliolatus var. unifoliolatus | 0–75 | – | ||
scarlet globemallow | SPCO | Sphaeralcea coccinea | 0–75 | – | ||
common yarrow | ACMI2 | Achillea millefolium | 0–45 | – | ||
onion | ALLIU | Allium | 0–45 | – | ||
pussytoes | ANTEN | Antennaria | 0–30 | – | ||
milkvetch | ASTRA | Astragalus | 0–30 | – | ||
wavyleaf thistle | CIUN | Cirsium undulatum | 0–30 | – | ||
bastard toadflax | COUM | Comandra umbellata | 0–30 | – | ||
sanddune wallflower | ERCAC | Erysimum capitatum var. capitatum | 0–30 | – | ||
scarlet beeblossom | GACO5 | Gaura coccinea | 0–30 | – | ||
bladderpod | LESQU | Lesquerella | 0–30 | – | ||
white heath aster | SYER | Symphyotrichum ericoides | 0–30 | – | ||
yellow salsify | TRDU | Tragopogon dubius | 0–30 | – | ||
bluebells | MERTE | Mertensia | 0–30 | – | ||
tufted evening primrose | OECAC2 | Oenothera caespitosa ssp. caespitosa | 0–30 | – | ||
purple locoweed | OXLA3 | Oxytropis lambertii | 0–30 | – | ||
phlox | PHLOX | Phlox | 0–30 | – | ||
upright prairie coneflower | RACO3 | Ratibida columnifera | 0–30 | – | ||
Missouri goldenrod | SOMI2 | Solidago missouriensis | 0–30 | – | ||
Shrub/Vine
|
||||||
7 | Shrubs | 0–45 | ||||
plains pricklypear | OPPO | Opuntia polyacantha | 0–45 | – | ||
brittle pricklypear | OPFR | Opuntia fragilis | 0–30 | – |
Table 8. Community 2.1 plant community composition
Group | Common name | Symbol | Scientific name | Annual production (lb/acre) | Foliar cover (%) | |
---|---|---|---|---|---|---|
Grass/Grasslike
|
||||||
1 | Western Wheatgrass | 440–640 | ||||
western wheatgrass | PASM | Pascopyrum smithii | 440–640 | – | ||
2 | Warm-Season Grasses | 0–40 | ||||
sideoats grama | BOCU | Bouteloua curtipendula | 0–24 | – | ||
blue grama | BOGR2 | Bouteloua gracilis | 0–24 | – | ||
3 | Needlegrasses | 0–80 | ||||
green needlegrass | NAVI4 | Nassella viridula | 0–80 | – | ||
4 | Native Grasses and Grass-likes | 0–24 | ||||
Grass, perennial | 2GP | Grass, perennial | 0–24 | – | ||
sedge | CAREX | Carex | 0–24 | – | ||
prairie Junegrass | KOMA | Koeleria macrantha | 0–24 | – | ||
Sandberg bluegrass | POSE | Poa secunda | 0–24 | – | ||
5 | Non-Native Grasses | 0–24 | ||||
cheatgrass | BRTE | Bromus tectorum | 0–24 | – | ||
Forb
|
||||||
6 | Forbs | 0–40 | ||||
sweetclover | MELIL | Melilotus | 0–40 | – | ||
scarlet globemallow | SPCO | Sphaeralcea coccinea | 0–24 | – | ||
American vetch | VIAM | Vicia americana | 0–24 | – | ||
Forb, annual | 2FA | Forb, annual | 0–24 | – | ||
curlycup gumweed | GRSQ | Grindelia squarrosa | 0–24 | – | ||
desert biscuitroot | LOFO | Lomatium foeniculaceum | 0–24 | – | ||
American bird's-foot trefoil | LOUNU | Lotus unifoliolatus var. unifoliolatus | 0–24 | – | ||
pennycress | MICRO18 | Microthlaspi | 0–24 | – | ||
leafy wildparsley | MUDI | Musineon divaricatum | 0–24 | – | ||
common yarrow | ACMI2 | Achillea millefolium | 0–16 | – | ||
onion | ALLIU | Allium | 0–8 | – | ||
pussytoes | ANTEN | Antennaria | 0–8 | – | ||
milkvetch | ASTRA | Astragalus | 0–8 | – | ||
wavyleaf thistle | CIUN | Cirsium undulatum | 0–8 | – | ||
bastard toadflax | COUM | Comandra umbellata | 0–8 | – | ||
sanddune wallflower | ERCAC | Erysimum capitatum var. capitatum | 0–8 | – | ||
scarlet beeblossom | GACO5 | Gaura coccinea | 0–8 | – | ||
tufted evening primrose | OECAC2 | Oenothera caespitosa ssp. caespitosa | 0–8 | – | ||
purple locoweed | OXLA3 | Oxytropis lambertii | 0–8 | – | ||
phlox | PHLOX | Phlox | 0–8 | – | ||
upright prairie coneflower | RACO3 | Ratibida columnifera | 0–8 | – | ||
Missouri goldenrod | SOMI2 | Solidago missouriensis | 0–8 | – | ||
bladderpod | LESQU | Lesquerella | 0–8 | – | ||
white heath aster | SYER | Symphyotrichum ericoides | 0–8 | – | ||
yellow salsify | TRDU | Tragopogon dubius | 0–8 | – | ||
bluebells | MERTE | Mertensia | 0–8 | – | ||
Shrub/Vine
|
||||||
7 | Shrubs | 0–40 | ||||
plains pricklypear | OPPO | Opuntia polyacantha | 0–40 | – | ||
brittle pricklypear | OPFR | Opuntia fragilis | 0–24 | – |
Interpretations
Hydrological functions
Water is the principal factor limiting herbage production on this site. The site is dominated by soils in hydrologic group D. Infiltration and runoff potential for this site varies from moderate to high depending on soil hydrologic group, slope and ground cover. In many cases, areas with greater than 75% ground cover have the greatest potential for higher infiltration and lower runoff. An exception would be where short grasses form a dense 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 Section 4, NRCS National Engineering Handbook for runoff quantities and hydrologic curves).
Recreational uses
This site provides hunting, hiking, photography, bird watching and other opportunities. The wide variety of plants that 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
Seed harvest of native plant species can provide additional income on this site.
Supporting information
Contributors
SCB
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 | Stan Boltz, stanley.boltz@sd.usda.gov, 605-352-1236 |
Date | 01/05/2010 |
Approved by | Stan Boltz |
Approval date | |
Composition (Indicators 10 and 12) based on | Annual Production |
Indicators
-
Number and extent of rills:
None. Soil cracking is natural and not caused by erosion. -
Presence of water flow patterns:
None, or barely visible and discontinuous. -
Number and height of erosional pedestals or terracettes:
None. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
5 to 30 percent is typical; the higher bare ground levels would appear during extended dry periods. -
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):
Litter should fall in place. 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 3 or greater. Surface organic matter usually adheres to the soil surface. Soil surface fragments will typically retain structure at least for short periods when dipped in distilled water. Some fragments will dissolve in less than 1 minute. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
A-horizon should be 3 to 6 inches thick but with light to dark gray colors when moist. Structure typically is platy parting to subangular blocky or occasionally fine granular in the upper 1/2 inch. -
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 rhizomatous grasses, tufted perennial cool-season grasses, and short warm-season grasses) with fine and coarse roots positively influences infiltration. Infiltration is not often affected by a change in plant composition as the rhizomatous cool-season species typically dominate. -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
A-horizon naturally has some platy structure. Compaction layers, if formed by management, do not typically persist. Compaction will be difficult to determine. Evidence of compaction can sometimes be confirmed by signs of recent concentration of livestock. -
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:
Rhizomatous wheatgrasses >>Sub-dominant:
Tall cool-season bunchgrasses >>Other:
Short warm-season grasses = forbs > 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):
Litter cover typically 20 to 60 percent, with the depth roughly 0.25 inches. -
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Total annual production ranges from 900 to 2,000 pounds/acre, with the reference value being 1,500 pounds/acre (air-dry basis). -
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. -
Perennial plant reproductive capability:
All species exhibit high vigor relative to climatic conditions. Do not rate based solely on seed production. Perennial grasses should have vigorous rhizomes or tillers.
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.