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Ecological site R062XY043SD

Valley Loam

Last updated: 8/20/2024
Accessed: 11/21/2024

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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.

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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): 062X–Black Hills

The Black Hills (MLRA 62) is a unique, low lying mountain range situated in the midst of a mixed short and mid-grass prairie. It is a true Island in the Plains, as it has geophysical and biological attributes that are unlike the surrounding area. The Black Hills have strong floristic ties to four of the North American biomes: Cordilleran (Rocky Mountain) Forest, Northern Coniferous Forest, Eastern Deciduous Forest, and Grasslands.

MLRA 62 is approximately 3,040 square miles in size; 74 percent is located in South Dakota, and 26 percent is in Wyoming. The towns of Lead, Deadwood, Hill City, and Custer, South Dakota, are in this area. U.S. Highways 16 and 385 cross the MLRA. The Black Hills National Forest, Custer State Park, Mt. Rushmore National Monument, Jewel Cave National Monument, and Wind Cave National Park are located in this MLRA.

This area forms the core of the Black Hills and the Bear Lodge Mountains where the elevation ranges between 3,600 to 6,565 feet, however, Black Elk Peak (Harney Peak) rises to 7,242 feet. Slopes range from moderately sloping on some of the high plateaus to very steeply sloping along drainageways and on peaks and ridges. Narrow valleys generally are gently sloping to strongly sloping.

The Black Hills uplift is the product of the Laramide mountain-building episodes that produced most of the ranges in the Rocky Mountains. Uplift began near the end of the Cretaceous period, 65 million years ago and ended by 35 million years ago (Froiland 1999). The core of the Black Hills is a plutonic mass of granite with steeply dipping metamorphic rocks, primarily slate and schist, which directly surrounds the granite core. A plateau of Mississippian limestone surrounds the igneous and metamorphic rock core. The Madison limestone is broken around the outer edges of the uplifted area. The Permian Minnekahta limestone forms the outermost boundary of the area. Many other tilted sandstone, shale, and limestone units are exposed like a bathtub ring inside the steeply dipping Madison limestone.

The dominant soil orders in this MLRA are Alfisols (forest soils) and Mollisols (grassland soils). The soils in the area have a frigid or cryic soil temperature regime, a udic or ustic soil moisture regime, and mixed, micaceous, or smectitic mineralogy. They are shallow to very deep, generally well drained, and loamy in texture.

The Black Hills MLRA supports open to dense forest vegetation. Ponderosa pine is the dominant species across the Black Hills. White spruce grows at the higher elevations and along the major drainageways. Bur oak is found intermixed with pine in the northern and eastern fringes of the Black Hills, and Rocky Mountain juniper is most common in the southern portion of the Black Hills. Aspen is of minor extent throughout the Black Hills area. Roughleaf ricegrass, slender wheatgrass, bearded wheatgrass, poverty oatgrass, Richardson’s needlegrass, and mountain ricegrass are the most common native grasses under open forest stands. The most common native shrubs are common snowberry, bearberry, common juniper, Oregon grape, and Saskatoon serviceberry.

MLRA 62 land ownership is approximately 47 percent private and 53 percent federal. Rangeland and forestland are split almost equally between private and federal ownership (47 percent each). Minor areas of land are privately owned cropland and urban development. The forestland in this area is used mainly for timber production, recreation, and grazing.

The major resource concerns are soil erosion and surface compaction caused by logging, mining, wildfires, grazing, and urban expansion. The quality of ground and surface water is another concern, especially in the northern part of the Black Hills. The primary cause is contamination from mine waste and septic systems in areas of rural development and urban expansion (USDA-NRCS, 2006: Ag Handbook 296).

LRU notes

For development of ecological sites, MLRA 62 is divided into three Land Resource Units (LRU’s) or physiographic zones (A, B, C, and Y). Each LRU has a set of ecological sites that represents these zones.

The LRU is identified in the Ecological Site ID: R062XY000SD; “062X” identifies the MLRA, the next letter “Y” identifies the LRU. Note: The organization of Ecological Site ID’s will likely change in the future.

LRU-A includes the northern Black Hills and Bear Lodge Mountains (22-30” PZ); LRU-B includes the high elevation central core of the Black Hills (25-35” PZ); and LRU-C includes the southern portion of the Black Hills (17-21” PZ).

The Forest ecological sites are representative of sites in the Black Hills, Bear Lodge Mountains (MLRA-62), and the surrounding Dakota Hogback (MLRA-61). These sites are separated by elevation, soil temperature regimes, and slope.

The Low Mountain area includes all of the Black Hills, Bear Lodge Mountains, and Dakota Hogback below 6,200 feet in elevation (LRU’s A and C). The soils in this area have a frigid soil temperature regime.

The High Mountain area includes all of the Black Hills above 6,200 feet elevation (LRU-B). The soils in this area have a cryic soil temperature regime.

Classification relationships

USDA
Land Resource Region G—Western Great Plains Range and Irrigated Region:
Major Land Resource Area (MLRA) 62—Black Hills

US Environmental Protection Agency (EPA)
Level IV Ecoregions of the Conterminous United States:
Black Hills Plateau—17b
Black Hills Core Highlands—17c

USDA Forest Service
Ecological Subregions: Sections and Subsections of Conterminous United States:
Black Hills Coniferous Forest Province—M334:
Black Hills Section—334A
Black Hills Limestone Plateau-Core Highlands Subsection—M334Ab

Ecological site concept

This site is located in flat “V-” or “U-” shaped mountain valleys within the Black Hills. It is not an overflow site but can receive some additional moisture from runoff from adjacent forested sites. The slopes range from 0 to 10 percent. Soils are deep (> 16” surface layer), well drained loam and silty loam. This site occurs throughout the MLRA, but the climate tends to be cooler and wetter in the north and higher elevations than in the south where it is warmer and dryer. Vegetation in the Reference community consists of nearly equal proportions of cool- and warm-season grass species, and forbs are common and diverse but never dominant. A patchy mosaic of shrubs such as western snowberry are almost always present across this ecological site, and aspen clones are common along the margins with forested sites.

Associated sites

R062XA020SD	Loamy Overflow - North The Loamy Overflow site (LRU-A) can be located adjacent to the Valley Loam site however the overflow site is directly influenced by addition water.
R062XB010SD	Loamy - High Central The Loam site (LRU-B) is located in Mountain Valleys that are dissected by low hills and hills slopes.
R062XC020SD	Loamy Overflow - South The Loamy Overflow site (LRU-C) can be located adjacent to the Valley Loam site however the overflow site is directly influenced by addition water.

R062XA020SD

Loamy Overflow - North

The Loamy Overflow site (LRU-A) can be located adjacent to the Valley Loam site however the overflow site is directly influenced by addition water.

R062XB010SD

Loamy - High Central

The Loam site (LRU-B) is located in Mountain Valleys that are dissected by low hills and hills slopes.

R062XC020SD

Loamy Overflow - South

The Loamy Overflow site (LRU-C) can be located adjacent to the Valley Loam site however the overflow site is directly influenced by addition water.

Similar sites

R062XC020SD	Loamy Overflow - South The Loamy Overflow site (LRU-C) will have higher production and is located adjacent to water.
R062XA020SD	Loamy Overflow - North The Loamy Overflow site (LRU-A) will have higher production and is located adjacent to water.
R062XB010SD	Loamy - High Central The Loam site (LRU-B) typically has a shallower soil surface layer, < 16 inch in depth, is located in Mountain Valleys that are dissected with low hills and hillslopes. The plant community has more cool-season grasses and few warm-season grasses and lower production.

R062XC020SD

Loamy Overflow - South

The Loamy Overflow site (LRU-C) will have higher production and is located adjacent to water.

R062XA020SD

Loamy Overflow - North

The Loamy Overflow site (LRU-A) will have higher production and is located adjacent to water.

R062XB010SD

Loamy - High Central

The Loam site (LRU-B) typically has a shallower soil surface layer, < 16 inch in depth, is located in Mountain Valleys that are dissected with low hills and hillslopes. The plant community has more cool-season grasses and few warm-season grasses and lower production.

Table 1. Dominant plant species

Tree	Not specified
Shrub	(1) Symphoricarpos occidentalis
Herbaceous	(1) Andropogon gerardii (2) Pascopyrum smithii

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Physiographic features

This site occurs on nearly level to sloping mountain valley landscapes in the Black Hills. The Mt Valley shape range from a flat "V" shape to a "U" shape, which is linear or slightly concave.

Table 2. Representative physiographic features

Landforms	(1) Mountain valley
Runoff class	Low to medium
Flooding frequency	None
Ponding frequency	None
Elevation	3,800 – 7,000 ft
Slope	10%
Water table depth	80 in
Aspect	Aspect is not a significant factor

Climatic features

MLRA 62 is in a microclimate caused by the influence of increased elevation, which leads to increased precipitation, moderate air temperature, and lower wind velocities as compared to the surrounding Great Plains. In general, the Black Hills climate is a continental type, cold in the winter and hot in the summer.

Annual precipitation in MLRA 62 typically increases with elevation and decreases from west to east and north to south. The average annual precipitation range for MLRA 62 is 17 to 35 inches: Land Resource Unit (LRU)-A (North) is 22 to 30 inches, LRU-B (Central High Country) is 25 to 35 inches and LRU-C (South) is 17 to 21 inches. Most of the rainfall occurs as frontal storms early in the growing season, in May and June. Some high-intensity, convective thunderstorms occur in July and August.

Precipitation in the winter occurs mostly as snow. The annual average snowfall ranges from 23 inches at the lower elevations in the south to 54 inches at the higher elevations in the central part of MLRA 62.

Average annual temperature ranges from 36 to 48 degrees F. January is the coldest month, with an average temperature of 22°F in the central part and 25°F in the southern part of MLRA 62. July is the warmest month, with an average daily temperature of 67°F in the central part and 73 F in the southern part of this MLRA.

The frost-free period ranges from 129 to 168 days. It is shortest at higher elevations and in the northwestern part of the MLRA.

Hourly winds are estimated to average about 11 miles per hour (mph) annually.

Growth of cool-season plants begins in April, slowing or ceasing growth by mid-August. Warm-season plants begin growth in May, and continue to mid-September. Regrowth of cool-season plants may occur in September and October, depending upon soil moisture availability.

Table 3. Representative climatic features

Frost-free period (characteristic range)	56-100 days
Freeze-free period (characteristic range)	90-119 days
Precipitation total (characteristic range)	20 in
Frost-free period (actual range)	27-108 days
Freeze-free period (actual range)	63-120 days
Precipitation total (actual range)	19-21 in
Frost-free period (average)	76 days
Freeze-free period (average)	102 days
Precipitation total (average)	20 in

Characteristic range

Actual range

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Figure 2. Monthly precipitation range

Characteristic range

Actual range

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Figure 3. Monthly minimum temperature range

Characteristic range

Actual range

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Figure 4. Monthly maximum temperature range

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Figure 5. Monthly average minimum and maximum temperature

Figure 6. Annual precipitation pattern

Figure 7. Annual average temperature pattern

Climate stations used

(1) WIND CAVE [USC00399347], Buffalo Gap, SD
(2) SUNDANCE [USC00488705], Sundance, WY
(3) DEERFIELD 3 SE [USC00392231], Hill City, SD
(4) CUSTER [USC00392087], Custer, SD

Soil features

The soils on this site are very deep and well drained. The surface layer is at least 16 inches thick, and commonly is deeper than 30 inches. Surface and subsurface textures are loamy (specific textures are listed below). The soils typically lack calcium carbonate above 40 inches. The slopes are typically 0 to 10 percent, but may range to 15 percent in a few areas.

Areas where slopes are less than about 3 percent typically are depositional areas. Unless the site is disturbed, the rate of deposition is roughly equal to or slightly greater than the rate of erosion. Water erosion is the primary hazard on this site. Erosion normally is minimal on slopes of less than 6 percent, and occurs primarily in the form of sheet erosion when present. Sheet and rill erosion are hazards on slopes greater than 6 percent. Although not common, gully erosion can become a hazard in areas of extreme disturbance, especially in areas of concentrated flow where slopes exceed 4 or 5 percent. Loss of 50 percent or more of the surface layer of the soils on this site can result in a shift in species composition and/or production. Although the soils on this site normally are not susceptible to significant wind erosion, site disturbances can increase the hazard locally.

The typical soil in LRU-A and C is Cordeston, and Crydeston in LRU-B.

Access Web Soil Survey (http://websoilsurvey.nrcs.usda.gov/app/) for specific local soils information.

Figure 8. Cordeston soil profile (cm)

Table 4. Representative soil features

Parent material	(1) Alluvium – limestone and sandstone
Surface texture	(1) Loam (2) Sandy loam
Family particle size	(1) Loamy
Drainage class	Well drained
Permeability class	Moderate
Soil depth	40 – 60 in
Surface fragment cover <=3"	1%
Surface fragment cover >3"	1%
Available water capacity (0-40in)	6 – 9 in
Calcium carbonate equivalent (0-40in)	Not specified
Electrical conductivity (0-40in)	2 mmhos/cm
Sodium adsorption ratio (0-40in)	1
Soil reaction (1:1 water) (0-40in)	5.6 – 7.8
Subsurface fragment volume <=3" (Depth not specified)	1 – 15%
Subsurface fragment volume >3" (Depth not specified)	1%

Ecological dynamics

Black Hills vegetation types consist of a mixture of forest and grasslands resulting from the varied topography, geology, soils, climate, and natural disturbances. Frequent fires, periodic drought, and episodic infestations of mountain pine beetles all contribute to the maintenance of large, open grasslands scattered throughout the Black Hills. Ponderosa pine is the dominant tree species in the Black Hills. It is a fire-adapted species that coexists with frequent, low-intensity fires that consume small seedlings, prune lower branches from larger trees, and reduce fuel loads on the forest floor.

This site developed under Black Hills climatic conditions with short-term weather variations; light to severe grazing by bison, elk, and small mammals; sporadic natural or man-caused wildfire (often of light intensities); and other biotic and abiotic factors that typically influence soil/site development. The natural fire regime maintained this site as a grassland and the plant communities were free of non-native cool-season grasses.

Fire, or the lack of fire, introduced non-native cool-season grasses, and defoliation (grazing and haying) are major drivers that shape this site as well as adjacent ecological sites. The Valley Loamy site does not appear to be as susceptible to conifer encroachment as other “upland” Loamy sites in MLRA 62, but it can occur. Aspen commonly occurs along the margins of this site, adjacent to forested sites. Kentucky bluegrass, timothy, and smooth brome are common non-native cool-season grass species throughout MLRA 62. Because the Black Hills have higher precipitation amounts and have cooler spring and fall periods, non-native cool-season grasses can easily become established and become the dominant species on this site.

The Reference State illustrates what is thought to have existed prior to European settlement. It is very difficult to locate a Reference plant community due to the introduction and spread of non-native cool-season grasses. Plant community phase 2.1 is most similar to the Reference State, but because of the persistence of non-native cool-season grasses, a restoration pathway to the Reference State is not believed to be achievable.

The following diagram illustrates the common plant community phases that can occur on the site, and the transition pathways between communities. These are the most common plant community phases based on current knowledge and experience, and changes will be made as more data is collected. Narratives following the diagram contain more detail pertaining to the ecological processes.

State and transition model

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Standard diagram

Figure 9. Valley Loam - 062XY043SD

Figure 10. Valley Loam - 062XY043SD

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Click on state and transition labels to scroll to the respective text

State 1
Reference State

This state represents what is believed to represent the natural range of variability and plant community dynamics of this ecological site prior to European settlement. The Reference State is unlikely to occur with the introduction of non-native cool-season grasses, which are common throughout the MLRA. This site was dominated by nearly equal portions of cool- and warm-season grasses, a diverse forb component, and various shrubs. In pre-European settlement times, the primary disturbances included fire and grazing by large ungulates and small mammals. Favorable growing conditions occurred during the spring, and the warm months of June and July. Routine and/or occasional fires removed pine encroachment, and contributed to the ecological processes that maintained the Reference plant community.

Community 1.1
Big Bluestem-Wheatgrass-Needlegrass/Mixed Shrubs

Interpretations are primarily based upon the Big Bluestem-Wheatgrass-Needlegrass/Mixed Shrubs plant community phase. This is considered to be the Reference or historic plant community. The potential vegetation is about 75 percent grass and grass-like plants, 15 percent forbs, and 10 percent shrubs. Total annual production for a normal growing year is approximately 3,000 lbs./ac. The community has nearly equal percentages of cool-season and warm-season grasses. The dominant warm-season grasses are big bluestem, prairie dropseed, and switchgrass. The principal cool-season grasses include western wheatgrass, bearded wheatgrass, slender wheatgrass, green needlegrass, Columbia needlegrass, and needleandthread. Other grasses and grass-like include Indiangrass, prairie Junegrass, porcupine grass, threadleaf sedge, and Richardson’s sedge. Forbs include stiff sunflower, stiff goldenrod, lupine, American vetch, yarrow, prairie smoke, and prairie coneflower. The dominant shrubs are western snowberry, willows, and Woods' rose. Aspen clones are common along the margin of the Valley Loam site adjacent to forested sites. This plant community was productive and resilient to disturbances such as drought and fire. It was a sustainable plant community in regard to soil/site stability, watershed function, and biological integrity.

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	2450	2624	2930
Forb	160	330	550
Shrub/Vine	160	246	350
Tree	30	100	170
Total	2800	3300	4000

Figure 12. Plant community growth curve (percent production by month). SD6208, Black Hills, lowland cool-season/warm-season co-dominant. Lowland 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	4	11	19	23	20	12	6	5	0	0

Community 1.2
Rhizomatous wheatgrass-Needlegrass/Mixed Shrubs

This plant community phase is the result of continuous season-long grazing without adequate recovery or continuous seasonal grazing during the early summer growing season every year. These grazing patterns will reduce the percentage of warm-season grasses and increase the percentage of cool-season grasses. Wet spring and fall precipitation patterns and dry summer months, in combination with grazing, can also cause a shift in the plant community toward a cool-season -dominated community. The removal of other natural disturbances, such as periodic fire and no-use, can cause a shift in the plant species to create a cool-season grass-dominated plant community. The potential vegetation consists of approximately 70 percent grasses and grass-likes, 15 percent forbs, and 15 percent shrubs and trees. The community is dominated by cool-season grasses, including western wheatgrass, bearded wheatgrass, slender wheatgrass, green needlegrass, needleandthread, and Columbia needlegrass. Warm-season grasses include big bluestem, prairie dropseed, and blue grama. Other grasses and grass-like plants in this phase include porcupine grass, prairie Junegrass, threadleaf sedge, and Richardson’s sedge. Forbs include goldenrod species, lupine, yarrow, prairie smoke, and prairie coneflower. Dominant shrubs include western snowberry, prairie rose, and hawthorn. Aspen clones are common along the margin of the Valley Loam site adjacent to forested sites. This plant community was productive and resilient to disturbances such as drought and fire. It’s a sustainable plant community in regard to soil/site stability, watershed function, and biological integrity.

Pathway 1.1A
Community 1.1 to 1.2

Long-term moderate to heavy grazing pressure without adequate recovery time, extended periods of below normal precipitation, and/or fire followed with intensive grazing by livestock or wildlife can move this PCP 1.1 to PCP 1.2.

Pathway 1.2A
Community 1.2 to 1.1

Grazing that provides adequate recovery, normal to above normal precipitation, and a normal fire regime without intensive grazing by livestock or wildlife can move PCP 1.2 back to PCP 1.1.

State 2
Native Invaded State

This state represents what is most typically found on this site. The natural range of variability is influenced by the presence of non-native cool-season grasses, especially smooth brome, Kentucky bluegrass, and timothy that can dominate the dynamics of this ecological site. Proper grazing management and periodic burning will maintain the productivity of this state. Heavy grazing without adequate recovery, excessive haying, and extended periods of non-use and no fire can put this state at risk of crossing a threshold to the Introduced/Invaded State.

Community 2.1
Rhizomatous wheatgrass-Big bluestem-Needlegrass-Bluegrass/Mixed Shrub

Figure 13. Valley Loam Plant Community Phase 2.1

This plant community phase closely resembles the PCP 1.1; however, non-native cool-season grasses have invaded the site and will persist in the plant community under the current Black Hills climatic conditions. The potential vegetation consists of about 75 percent grass and grass-like plants, 15 percent forbs, and 10 percent shrubs and trees. Total annual production for a normal growing year is approximately 2,800 lbs./ac. The community is dominated by cool-season grasses and tall and mid-height warm-season grasses. The dominant cool-season grasses include western and bearded wheatgrass, green needlegrass, needleandthread, and porcupine grass. Kentucky bluegrass and/or other non-native cool-season grasses can make up 2 to 5 percent of the plant community. Dominant warm-season grasses are big bluestem, prairie dropseed, and switchgrass. Other grasses include slender wheatgrass, Richardson’s needlegrass, thread-leaf sedge, and Richardson’s sedge. The dominant shrubs are western snowberry, willows, and rose. This plant community is productive and resilient to disturbances such as drought and fire. It is a sustainable plant community in regard to soil/site stability, watershed function, and biological integrity. Management strategies must include techniques that will not cause Kentucky bluegrass and other non-native cool-season grasses to increase significantly, as this could put the plant community at risk of transition to the Introduced/Invaded State.

Community 2.2
Rhizomatous wheatgrass-Bluegrass-Smooth brome/Weedy forbs/Mixed Shrubs

This plant community evolved under continuous season-long grazing, or seasonal grazing with no change in season of use, or no use and no fire, or heavy continuous grazing that exceeds carrying capacity, or excessive haying. This plant community phase is made up of approximately 85 percent grass and grass-like plants, 10 percent forbs, and 5 percent shrubs and trees. The community is dominated by cool-season grasses, with most of the warm-season grass component replaced by smooth brome and Kentucky bluegrass, along with other non-native cool-season grasses. The dominant cool-season grasses include western and bearded wheatgrass, Richardson’s needlegrass. Kentucky bluegrass or other non-native cool-season grasses can make up 10 to 20 percent of the plant community. Forbs may tend to be weedy and invasive. Common shrubs include western snowberry and green sagewort. This plant community is at risk of crossing a threshold to the Introduced/Invaded State.

Pathway 2.1A
Community 2.1 to 2.2

Non-use and no fire and/or continuous season-long grazing or seasonal grazing occurring at the same time every year, or heavy continuous grazing or excessive haying will cause an increase in non-native cool-season grass species moving this plant community to PCP 2.2.

Pathway 2.2A
Community 2.2 to 2.1

Prescribed grazing and forage harvest management that provides adequate recovery and change in season of use, along with normal precipitation regime and fire may reduce the percent of non-native cool-season grasses in PCP 2.2 and restore the tall warm-season component typical of PCP 2.1.

State 3
Introduced/Invaded State

This state is the result of invasion and dominance of non-native species. This state is characterized by the dominance of smooth brome, Kentucky bluegrass, and timothy in the plant communities. These species will out-compete and replace the native bluestems, needlegrasses, and wheatgrasses. The nutrient cycle is impaired, which results in a higher level of nitrogen that favors the introduced species. Studies indicate that soil biological activity is altered, and this shift apparently exploits the soil microclimate and encourages growth of the non-native grass species. Preliminary studies indicate when Kentucky bluegrass exceeds 30 percent of the plant community and native grasses represent less than 40 percent of the plant community composition, a threshold has been crossed to an Invaded State (3.0). Plant communities dominated by Kentucky bluegrass have significantly less cover and diversity of native grasses and forb species. (Toledo, D. et al., 2014). Once the threshold is crossed, a change in grazing management alone cannot cause a reduction in the invasive grass dominance.

Community 3.1
Smooth brome-Kentucky bluegrass /Weedy forbs/Mixed shrubs

Figure 14. Valley Loam Plant Community Phase 3.1

This plant community is dominated by smooth brome, Kentucky bluegrass, and/or other non-native cool-season grasses making up 30 percent or more of the plant community. This plant community evolved under no use and no fire, or with heavy continuous season-long grazing, or seasonal grazing with no change in season of use, or excessive haying. This plant community is made up of approximately 85 percent grasses and grass-like species, 10 percent forbs, and 5 percent shrubs. While the non-native grasses are dominant, rhizomatous wheatgrass and needlegrass remnants may still be found in the plant community. Forbs commonly found in this plant community include cudweed sagewort, goldenrod, and western ragweed. Production will be significantly reduced when compared to the interpretive plant community. The period when palatability is high is relatively short, as smooth brome and Kentucky bluegrass mature rapidly. Energy capture is also reduced. Runoff is high and biological activity in the soil likely is reduced significantly in this phase.

State 4
Early Seral State

This state is the result of very heavy disturbance such as cropping, concentrated livestock feeding areas, or rodent activity. This state can develop as a result of invasion by highly competitive weed species such as Canada thistle, hound’s tongue, leafy spurge, or knapweeds. Heavy grazing also can push an at-risk plant community phase to this state. In most cases, this phase is dominated by annual and/or pioneer perennial species. The percentage of bare ground is typically much higher than on any other plant community phase.

Community 4.1
Pioneer Perennial/Introduced Species, Bare Ground

This plant community developed under continuous heavy grazing or heavy disturbances such as heavy use areas, abandoned cropland, and livestock feeding areas. The potential plant community is made up of 60-80 percent grasses and grass-like species, 15 to 35 percent forbs, and 2 to 5 percent shrubs. The percentage of bare ground can be very high in this plant community. Dominant grass is often smooth brome and/or Kentucky bluegrass. Other grasses may include annual bromegrass (field brome and cheatgrass), sedge, sand dropseed, and western wheatgrass. The dominant forbs include fetid marigold, sweetclover, western ragweed, cudweed sagewort, and other invasive species. The dominant shrubs include fringed sagewort and broom snakeweed. A wide variety of other early seral plant species can occupy this site in varying amounts. This plant community is susceptible to invasion of Canada thistle and other non-native species because of the relatively high percentage of bare ground.

Transition 1A
State 1 to 2

Invasion and/or encroachment of non-native grasses such as Kentucky bluegrass, smooth brome, and timothy, and disruption of natural disturbance regimes, typically as a result of fire suppression following settlement, led this state over a threshold to the Native Invaded State 2.0.

Transition 2A
State 2 to 3

Introduction or increase of non-native cool season grass species in the plant community. Non-use and no fire. Excessive haying of native grass species and or heavy continuous grazing. This transition is most likely going to occur from PCP 2.2

Transition 2B
State 2 to 4

Severe and frequent defoliation, which can be exacerbated by drought and/or additional livestock or wildlife use. Heavy disturbance areas, including livestock feeding areas and cropping, also can cause this transition to the Early Seral State.

Restoration pathway 3A
State 3 to 2

Early season prescribed burning followed by long term prescribed grazing to promote establishment of native species. Chemical and/or mechanical treatment followed by seeding of native species may accelerate the reestablishment of structural functional groups similar to PCP 2.1, but the resulting plant community may not achieve management goals. This restoration pathway can take many years and may not be successful in the end.

Transition 3A
State 3 to 4

Severe and frequent defoliation, livestock feeding, heavy disturbance, excessive haying and cropping will push this plant community to the Early Seral State.

Restoration pathway 4A
State 4 to 2

Removal of severe grazing disturbance (frequency and intensity), normal precipitation and fire regime, and time. Chemical and/or mechanical treatment followed by seeding of native species may accelerate the reestablishment of structural/functional groups similar to PCP 2.1; however, the resulting plant community may not achieve management goals. This restoration pathway can take many years and may not be successful in the end.

Transition 4A
State 4 to 3

Removal of severe grazing disturbance (frequency and intensity) and normal precipitation regime. Chemical and/or mechanical treatment followed by seeding can transition this plant community back to the Introduced/Invaded State.

Additional community tables

Table 6. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production (lb/acre)	Foliar cover (%)
Grass/Grasslike
1	Tall & Mid- Warm-Season Grasses			330–990
	big bluestem	ANGE	Andropogon gerardii	330–660	–
	marsh muhly	MURA	Muhlenbergia racemosa	0–165	–
	prairie cordgrass	SPPE	Spartina pectinata	33–165	–
	prairie dropseed	SPHE	Sporobolus heterolepis	33–165	–
	Indiangrass	SONU2	Sorghastrum nutans	0–66	–
	switchgrass	PAVI2	Panicum virgatum	0–33	–
2	Rhizomatous Wheatgrass			165–330
	western wheatgrass	PASM	Pascopyrum smithii	165–330	–
	thickspike wheatgrass	ELLAL	Elymus lanceolatus ssp. lanceolatus	0–165	–
3	Cool-Season Bunchgrass			660–1155
	slender wheatgrass	ELTRS	Elymus trachycaulus ssp. subsecundus	66–330	–
	green needlegrass	NAVI4	Nassella viridula	66–330	–
	slender wheatgrass	ELTR7	Elymus trachycaulus	66–330	–
	needle and thread	HECOC8	Hesperostipa comata ssp. comata	66–165	–
	porcupinegrass	HESP11	Hesperostipa spartea	0–66	–
	roughleaf ricegrass	ORAS	Oryzopsis asperifolia	0–66	–
	Virginia wildrye	ELSU	Elymus submuticus	0–66	–
	inland bluegrass	PONEI2	Poa nemoralis ssp. interior	0–66	–
	Canada wildrye	ELCA4	Elymus canadensis	33–66	–
	Columbia needlegrass	ACNE9	Achnatherum nelsonii	33–66	–
	fowl bluegrass	POPA2	Poa palustris	0–66	–
4	Other Native Grasses			0–165
	Grass, perennial	2GP	Grass, perennial	0–165	–
	downy ryegrass	LEIN6	Leymus innovatus	0–66	–
	mountain brome	BRMA4	Bromus marginatus	0–66	–
5	Grass-Likes			165–330
	clustered field sedge	CAPR5	Carex praegracilis	33–165	–
	Grass-like (not a true grass)	2GL	Grass-like (not a true grass)	0–165	–
	shortbeak sedge	CABR10	Carex brevior	0–66	–
	Sprengel's sedge	CASP7	Carex sprengelii	0–66	–
	sun sedge	CAINH2	Carex inops ssp. heliophila	33–66	–
6	Non-Native Cool-Season Grasses			0
Forb
7	Forbs			165–495
	goldenrod	SOLID	Solidago	66–165	–
	mint	MENTH	Mentha	66–165	–
	cinquefoil	POTEN	Potentilla	33–165	–
	white sagebrush	ARLU	Artemisia ludoviciana	33–66	–
	dotted blazing star	LIPU	Liatris punctata	0–66	–
	fleabane	ERIGE2	Erigeron	0–66	–
	beardtongue	PENST	Penstemon	0–66	–
	prairie clover	DALEA	Dalea	0–66	–
	upright prairie coneflower	RACO3	Ratibida columnifera	0–66	–
	scurfpea	PSORA2	Psoralidium	33–66	–
	western yarrow	ACMIO	Achillea millefolium var. occidentalis	33–66	–
	white prairie aster	SYFA	Symphyotrichum falcatum	0–66	–
	Forb, native	2FN	Forb, native	33–66	–
	American licorice	GLLE3	Glycyrrhiza lepidota	33–66	–
	bellflower	CAMPA	Campanula	0–66	–
	bluebells	MERTE	Mertensia	0–66	–
	milkvetch	ASTRA	Astragalus	33–66	–
Shrub/Vine
8	Shrubs			165–330
	Bebb willow	SABE2	Salix bebbiana	33–165	–
	redosier dogwood	COSE16	Cornus sericea	33–165	–
	western snowberry	SYOC	Symphoricarpos occidentalis	66–165	–
	Woods' rose	ROWO	Rosa woodsii	33–66	–
	yellow willow	SALU2	Salix lutea	0–66	–
	Shrub (>.5m)	2SHRUB	Shrub (>.5m)	0–66	–
	Saskatoon serviceberry	AMAL2	Amelanchier alnifolia	33–66	–
	currant	RIBES	Ribes	0–66	–
	chokecherry	PRVI	Prunus virginiana	0–66	–
	sandbar willow	SAIN3	Salix interior	0–33	–
Tree
9	Deciduous Trees			33–165
	green ash	FRPE	Fraxinus pennsylvanica	33–66	–
	narrowleaf cottonwood	POAN3	Populus angustifolia	33–66	–
	quaking aspen	POTR5	Populus tremuloides	0–33	–
	Tree	2TREE	Tree	0–33	–
	boxelder	ACNE2	Acer negundo	0–33	–
	bur oak	QUMA2	Quercus macrocarpa	0–33	–
10	Conifer Trees			0–33
	ponderosa pine	PIPO	Pinus ponderosa	0–33	–
	white spruce	PIGL	Picea glauca	0–33	–
	Tree	2TREE	Tree	0–33	–

Interpretations

Other information

Revision Notes:
This PROVISIONAL ecological site concept has been QCd and QAd to ensure that the site meets the NESH standards for a provisional ecological site that provides basic compiled information in one location. This site should not be considered an Approved ESD, as it is only the foundational site concepts and requires further data collection—specifically high-intensity data characterizations and full 232 soil descriptions—and further site investigations and final STM reviews before it can be used as an Approved ESD meeting NESH standards. This site is new to the MLRA but was previously included in the High Country Silty Range Site 062XY033SD in the South Dakota FOTG. Site Development and Testing Plan:

Future work, as described in a Project Plan, to validate the information in this Provisional Ecological Site Description is needed. 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. A final field review, peer review, quality control, and quality assurance reviews of the ESD will be needed to produce the final document.

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 were also used. Those involved in developing this site include: Lakhdar Benkobi, ESI/SRIC, NRCS; Stan Boltz, Range Management Specialist, NRCS; Dan Brady, Soil Scientist, NRCS; Mitch Faulkner, Range Management Specialist, NRCS; Roger Gates, Associate Professor/Rangeland Management Specialist, West River Ag Center; Rick Peterson, Ecological Site Specialist, NRCS; Matthew, Scott, Botanist - USFS Hell Canyon District Ranger; L. Michael Stirling, Range Management Specialist, NRCS; Jim Westerman, Soil Scientist, NRCS. All inventory information and data records are compiled within the Rapid City, SD USDA-NRCS Shared “S” network drive.

Other references

High Plains Regional Climate Center, University of Nebraska. http://www.hprcc.unl.edu/)

Toledo, D., M. Sanderson, K. Spaeth., J. Hendrickson, J. Printz. 2014. Extent of Kentucky bluegrass and its effect on native plant species diversity and ecosystem services in the Northern Great Plains of the United States. Invasive Plant Science and Management. 7(4):543-522. Weed Science Society of America.

USDS, NRCS. 2006. Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296.

USDA, NRCS. National Water and Climate Center. (http://wcc.nrcs.usda.gov)

USDA, NRCS. National Range and Pasture Handbook. September, 1997

USDA, NRCS. National Soil Information System, Information Technology Center. (http://nasis.nrcs.usda.gov)

USDA, NRCS. 2001. The PLANTS Database, Version 3.1 (http://plants.usda.gov). National Plant Data Center.

USDA, NRCS. National Ecological Site Handbook. 1st Ed, January, 2014.

Contributors

Peterson Rick L.
Westerman James

Approval

Suzanne Mayne-Kinney, 8/20/2024

Acknowledgments

All ecological sites were then reviewed and approved at the Provisional Level by David Kraft, Regional ESS, Salina, KS in September 2020.

Rangeland health reference sheet

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

Author(s)/participant(s)
Contact for lead author
Date	08/23/2024
Approved by	Suzanne Mayne-Kinney
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

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

Dominant:

Sub-dominant:

Other:

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

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Natural ResourcesConservation Service

Ecological site R062XY043SD

Valley Loam

Last updated: 8/20/2024 Accessed: 11/21/2024

General information

Figure 1. Mapped extent

MLRA notes

LRU notes

Classification relationships

Ecological site concept

Associated sites

Similar sites

Table 1. Dominant plant species

Ecosystem states

State 1 submodel, plant communities

State 2 submodel, plant communities

State 3 submodel, plant communities

State 4 submodel, plant communities

Natural Resources
Conservation Service

Last updated: 8/20/2024
Accessed: 11/21/2024