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Ecological site R058AY730MT

Ponderosa Pine 15-19

Last updated: 8/29/2024
Accessed: 09/05/2026

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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.

MLRA notes

Major Land Resource Area (MLRA): 058A–Northern Rolling High Plains, Northern Part

MLRA 058A, Northern Rolling High Plains (Northern Part), is an expansive and agriculturally and ecologically significant area encompassing 26 counties in southeast Montana (99 percent) and northeast Wyoming (1 percent). It stretches approximately 290 miles from east to west and 220 miles from north to south and comprises approximately 42,350 square miles (26,875,928 acres). The area is within the Missouri Plateau, Unglaciated, Section of the Great Plains Province of the Interior Plains. It is an area of old plateaus and terraces that have been eroded. Slopes generally are gently rolling to steep, and wide belts of steeply sloping badlands border a few of the larger river valleys. In some areas flat-topped, steep-sided buttes rise sharply above the general level of the plains. Elevations generally range from 2,950 to 3,280 feet, increasing from east to west and from north to south.

Tertiary continental shale, siltstone, and sandstone of the Fort Union Formation underlie the eastern one-third to one-half of this area. Marine and continental sediments of the Cretaceous Montana Group underlie the rest of the MLRA, generally at the higher elevations. There are also younger Cretaceous sediments of the Livingston Group occurring between the higher elevation Montana Group sediments and the lower elevation Tertiary sediments. The dominant soil orders in MLRA 058A are Entisols and Inceptisols. The soils in the area dominantly have a frigid soil temperature regime, an ustic soil moisture regime, and mixed or smectitic mineralogy. They range from shallow to very deep and are generally well drained and clayey or loamy.

The area primarily supports native prairie vegetation characterized by a variety of cool-season and warm-season graminoids, forbs, and shrubs. In the western portion of the area, cool-season grasses such as western wheatgrass and bluebunch wheatgrass are dominant but, in the eastern portion of the area, warm-season grasses such as little bluestem and sideoats grama become dominant. Wyoming big sagebrush, silver sagebrush, and fringed sagewort are common shrub species throughout the area. Forested areas occur in rough hilly areas and river breaks, particularly in areas with higher precipitation. Common tree species are ponderosa pine and Rocky Mountain juniper with scattered pockets of Douglas fir.

More than 75 percent of this MLRA is native rangeland utilized for livestock production and more than 50 percent of the MLRA consists of privately-owned ranches. Approximately 15 percent of the MLRA is used as cropland. Other land uses including forestland, urban development, water, and other uses combine for less than 10 percent of the total land use.

Classification relationships

NRCS Soil Geography Hierarchy
• Land Resource Region: Western Great Plains
• Major Land Resource Area (MLRA): 058A Northern Rolling High Plains, Northern Part

National Hierarchical Framework of Ecological Units (Cleland et al., 1997; McNab et al., 2007)
• Domain: Dry
• Division: Temperate Steppe
• Province: Great Plains-Palouse Dry Steppe Province (331)
• Section: North Central Highlands (331K) and Powder River Basin (331G)

National Vegetation Classification Standard (Federal Geographic Data Committee, 2008)
• Class: Forest and Woodland Class (1)
• Subclass: Temperate and Boreal Forest and Woodland Subclass (1.B)
• Formation: Cool Temperate Forest and Woodland Formation (1.B.2)
• Division: Rocky Mountain Forest and Woodland Division (1.B.2.Nb)
• Macrogroup: Central Rocky Mountain Dry Lower Montane-Foothill Forest (1.B.2.Nb.2)
• Group: Black Hills-Northwestern Great Plains Ponderosa Pine Forest and Woodland (1.B.2.Nb.2.e)
• Alliance: Northwest Great Plains Ponderosa Pine Open Woodland

EPA Ecoregions
• Level 1: Great Plains (9)
• Level 2: West-Central Semi-Arid Prairies (9.3)
• Level 3: Northwestern Great Plains (9.3.3)
• Level 4: Montana Central Grasslands (43n), River Breaks (43c), and Pine Scoria Hills (43p)

Ecological site concept

This ecological site occurs primarily on ridges, hills, and escarpments at elevations ranging from 1,900 to 3,500 feet and on slopes ranging from 5 to 60 percent. Occurrences are generally on east and north facing aspects, but aspect may vary. The soils of this ecological site range from shallow to very deep, but the majority are typically shallow to moderately deep. Soil textures on this ecological site vary widely and may range from loamy sands or sandy loams to clay loam or clay.

Associated sites

R058AY726MT	Woody Draw 15-19 This site occurs on moderate to steeply sloping hillslopes adjacent to and downslope from the Ponderosa Pine ecological site. It occurs in steep, v-shaped swales that receive additional moisture from run-in.
R058AY733MT	Shallow 15-19 This site occurs on nearly level to steeply sloping uplands that are adjacent to or upslope from the Ponderosa Pine ecological site. It occurs on upper backslope, crest, or summit positions where soils are 10 to 20 inches deep.
R058AY735MT	Very Shallow 15-19 This site occurs on nearly level to steeply sloping uplands that are adjacent to or upslope from the Ponderosa Pine ecological site. It occurs on upper backslope, crest, or summit positions where soils are less than 10 inches deep and is often associated with rock outcrops.

R058AY726MT

Woody Draw 15-19

This site occurs on moderate to steeply sloping hillslopes adjacent to and downslope from the Ponderosa Pine ecological site. It occurs in steep, v-shaped swales that receive additional moisture from run-in.

R058AY733MT

Shallow 15-19

This site occurs on nearly level to steeply sloping uplands that are adjacent to or upslope from the Ponderosa Pine ecological site. It occurs on upper backslope, crest, or summit positions where soils are 10 to 20 inches deep.

R058AY735MT

Very Shallow 15-19

Similar sites

R058AY701MT	Clayey 10-14 This site differs from the Ponderosa Pine ecological site in that soils receive additional moisture from run-in and support primarily deciduous vegetation.
R058AY715MT	Sandy 10-14 This site differs from the Ponderosa Pine ecological site in that it occurs where soils are drier and do not support on overstory of trees. It typically occurs on south and west aspects, but aspect may vary.

R058AY701MT

Clayey 10-14

This site differs from the Ponderosa Pine ecological site in that soils receive additional moisture from run-in and support primarily deciduous vegetation.

R058AY715MT

Sandy 10-14

This site differs from the Ponderosa Pine ecological site in that it occurs where soils are drier and do not support on overstory of trees. It typically occurs on south and west aspects, but aspect may vary.

Table 1. Dominant plant species

Tree	(1) Pinus ponderosa
Shrub	Not specified
Herbaceous	(1) Pseudoroegneria spicata (2) Schizachyrium scoparium

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Physiographic features

This ecological site occurs on many upland positions including sedimentary plains, ridges, hills, and escarpments. This ecological site occurs on gently sloping to very steep slopes. Slopes may range from 5 to 60 percent but are typically between 15 and 45 percent. It occurs on all exposures, and aspect sometimes becomes significant, particularly on steeper slopes. Variations in the understory plant community composition and production can result due to aspect.

Table 2. Representative physiographic features

Landforms	(1) Plain (2) Ridge (3) Hill (4) Escarpment
Runoff class	Low to medium
Flooding frequency	None
Ponding frequency	None
Elevation	1900 – 3500 ft
Slope	15 – 45 %
Aspect	W, NW, N, NE, E, SE, S, SW

Table 3. Representative physiographic features (actual ranges)

Runoff class	Not specified
Flooding frequency	Not specified
Ponding frequency	Not specified
Elevation	0 ft
Slope	5 – 60 %

Climatic features

MLRA 058A is a semi-arid region and is considered to have a continental climate characterized by cold winters, hot summers, low humidity, light rainfall, and much sunshine. The climate is the result of the MLRA’s location in the geographic center of North America. Temperatures can be extreme. The average annual temperature is 41 to 49 degrees Fahrenheit. Summer daytime temperatures are typically quite warm, generally averaging in the lower to mid 80 degree range for July and August. Summertime temperatures will typically reach 100 degrees or more at some point during the summer and can reach 90 degrees during any month between May and September. Conversely, winter temperatures can be cold, averaging in the lower teens or less for December and January. There will typically be several days of below zero temperatures each winter. It is not uncommon for temperatures to reach 30 to 40 degrees below zero, or even colder, most any winter.

During an average year, 70 to 75 percent of the annual precipitation falls between April and September, which are the primary growing season months. Most of the rainfall occurs as frontal storms early in the growing season during the months of May and June. Some high-intensity, convective thunderstorms occur in July and August, and some rainfall occurs in autumn. Later summer precipitation is greater in the eastern portion of the MLRA, which effects plant community composition. Winter precipitation occurs as snow although snowfall is not heavy, averaging about 39 inches annually, and snow cover is typically 1 to 3 inches. Heavy snowfall occurs infrequently, usually late in the winter or early spring. The average annual precipitation ranges from 8 to 22 inches but is typically 15 to 19 inches throughout most of the area where this ecological site exists. Precipitation fluctuates widely from year to year and severe drought occurs 2 out of 10 years on average.

There are few natural barriers on the northern Great Plains and the winds move freely across the plains and account for rapid changes in temperature. Spring can be windy throughout the MLRA, with winds averaging over 10 mph about 15 percent of the time. Speeds of 50 mph or stronger can occasionally occur. During the winter months, the western half of the MLRA commonly experiences Chinook winds, which are strong west to southwest surface winds accompanied by abrupt increases in temperature. The Chinook winds are strongest on the western boundary of the MLRA near the Rocky Mountain foothills and decrease eastward. In addition to producing damaging winds, prolonged Chinook episodes can result in drought or vegetation kills due to a reaction of plants to a “false spring” (Oard, 1993).

For local climate station information, refer to https://wrcc.dri.edu/summary/Climsmemt.html.

Table 4 Representative climatic features

Frost-free period (characteristic range)	70-150 days
Freeze-free period (characteristic range)	90-180 days
Precipitation total (characteristic range)	20-20 in
Frost-free period (average)	120 days
Freeze-free period (average)	140 days
Precipitation total (average)	20 in

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Figure 1. Monthly precipitation range

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Line

Figure 2. Monthly average minimum and maximum temperature

Figure 3. Annual precipitation pattern

Figure 4 Annual average temperature pattern

Climate stations used

(1) WINIFRED [USC00249033], Hilger, MT
(2) COLUMBUS [USC00241938], Columbus, MT
(3) WYOLA 1 SW [USC00249175], Wyola, MT
(4) EKALAKA [USC00242689], Ekalaka, MT
(5) MELSTONE [USC00245596], Musselshell, MT
(6) YELLOWTAIL DAM [USC00249240], Lodge Grass, MT

Influencing water features

This is upland ecological site and is not influenced by a water table or run in from adjacent sites. Due to the semi-arid climate in which it occurs, the water budget is normally contained within the soil pedon. Soil moisture is recharged by spring rains, but it but rarely exceeds field capacity in the upper 40 inches before being depleted by evapotranspiration. During intense precipitation events, precipitation rates frequently exceed infiltration rates and this site delivers moisture to downslope sites via surface runoff. Moisture loss through evapotranspiration exceeds precipitation for the majority of the growing season and soil moisture is the primary limiting factor for plant production on this ecological site.

Wetland description

Not Applicable

Soil features

Soils for this ecological site are typically shallow or moderately deep (10 to 40 inches to bedrock) but may vary from shallow to very deep depending on slope, aspect, and annual precipitation. They are typically well drained and derived from residuum from interbedded sandstone and shale. A thin (0 to 1 inches) organic horizon comprised of forest litter and fibric materials is typically present on the soil surface. Surface mineral horizon textures are typically loam and the underlying horizons typically have loamy sand, sandy loam, loam, silt loam, clay loam, or silty clay loam textures. Some soil profiles may contain a horizon of leaching below the mineral soil surface layer or pieces of charcoal from past fires. The soil temperature regime is primarily frigid, with smaller areas of mesic temperature regime present. The soil moisture regime is typic ustic. The following Figure shows a typical soil profile for this ecological site.

Figure 5. Typical Soil Profile

Table 5. Representative soil features

Parent material	(1) Residuum – sandstone and shale
Surface texture	(1) Loam
Drainage class	Well drained
Permeability class	Moderate
Soil depth	10 – 72 in
Surface fragment cover <=3"	Not specified
Surface fragment cover >3"	0 – 0.1 %
Available water capacity (0-15in)	2 – 2.2 in
Electrical conductivity (0-15in)	0 – 8 mmhos/cm
Sodium adsorption ratio (0-15in)	Not specified
Soil reaction (1:1 water) (0-15in)	6.6 – 9
Subsurface fragment volume <=3" (0-15in)	0 – 30 %
Subsurface fragment volume >3" (0-15in)	0 – 5 %

Ecological dynamics

Interpretations are primarily based on the Reference state, which is used as a reference in order to understand the original potential of the site. This ecological site developed under the combined influences of climatic conditions, periodic fire activity, grazing by large herbivores, and impacts from small mammals and insects. Changes may occur to the Reference state due to management actions such as improper grazing management, climatic conditions such as drought, natural events such as catastrophic fire, or the absence of low-intensity, natural or prescribed fire. The reference state for this ecological site is an open, widely spaced overstory of ponderosa pine with a herbaceous understory dominated by a diversity of medium height, cool-season and warm-season grasses, which are tightly intermixed and well distributed over the site. Various forbs, half-shrubs, and shrubs are common on this site. Periodic low intensity fire limits woody plant recruitment and maintains an open tree canopy. The Reference state is not necessarily the management goal, as other vegetative states may be considered desired plant communities as long as critical resource concerns are met.

In addition to the Reference state, other plant communities can occur on this site and are usually the result of historic management practices. Long-term fire suppression allows for a closed tree canopy with an increase in shrubs such as Rocky Mountain juniper and a decrease in the herbaceous component. Catastrophic wildfire results in a near complete removal of vegetation with grasses generally recovering within a few years and the trees requiring decades or longer for recovery. Long term overgrazing on this ecological site results in a decrease of mid-grasses and more palatable forbs and in an increase of shortgrasses, sedges, and less palatable forbs. There are various transitional stages which may occur on this ecological site.

State and transition model

More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective text

Ecosystem states

T1A	-	Intensive Fire Suppression
T1B	-	High Intensity, Stand Replacing Fire
R2A	-	Aggressive thinning and removal of trees (Brush Management, harvesting, etc.), Prescribed Fire, Herbaceous Weed Control (management intensive and costly)
T2A	-	High Intensity, Stand Replacing Fire
T3C	-	Long-term tree regrowth and return to historic fire frequency/intensity
T3A	-	Prolonged drought, Improper grazing management, or a combination of these factors
T3B	-	Displacement of native species by non-native invasive species (Kentucky bluegrass, annual bromes, noxious weeds, etc.)
R4A	-	Proper grazing management in combination with range planting, intensive weed management (management intensive and costly)

State 1 submodel, plant communities

1.1. Mature, Open Savanna

1.2. Young, Open Savanna

1.3. Seedling/Shrub

1.2A	-	Tree growth in combination with periodic low intensity fire
1.3A	-	Tree growth in combination with periodic low intensity fire

State 2 submodel, plant communities

2.1. Young, Dense Forest

2.2. Mature, Dense Forest

2.1A	-	Long term fire suppression, tree growth, and shrub encroachment

State 1
Reference

The Reference state for this ecological site consists of three communities and evolved under the combined influences of climatic conditions, periodic fire activity, grazing by large herbivores, and impacts from small mammals and insects. The Reference state is the plant communities in which interpretations are primarily based and is used as a reference in order to understand the original potential of the site.

Dominant plant species

ponderosa pine (Pinus ponderosa), tree
bluebunch wheatgrass (Pseudoroegneria spicata), grass

Community 1.1
Mature, Open Savanna

This plant community is characterized by a mature ponderosa pine community with tree diameters at nine inches DBH and greater. The understory is dominated by bunchgrasses such as bluebunch wheatgrass, little bluestem, sideoats grama, needle and thread, and pinegrass. Shortgrasses such as blue grama, prairie Junegrass, threadleaf sedge, and sun sedge occur at low canopy cover.

Community 1.2
Young, Open Savanna

This plant community is characterized by a young ponderosa pine community with tree diameters from 1 to 9 inches DBH. The understory is dominated by bunchgrasses such as bluebunch wheatgrass, little bluestem, sideoats grama, needle and thread, and pinegrass. Shortgrasses such as blue grama, prairie Junegrass, threadleaf sedge, and sun sedge occur at low canopy cover.

Community 1.3
Seedling/Shrub

This plant community is characterized by a ponderosa pine community dominated by seedlings with tree diameters less than one inch. A variety of shrubs in a low growth form are common in this community phase including serviceberry, snowberry, chokecherry, skunkbush sumac, yucca, Rocky Mountain juniper, creeping juniper, and creeping barberry. The herbaceous layer is comprised of mixed-grasses including species such as bluebunch wheatgrass, needle and thread, western wheatgrass, little bluestem, sideoats grama, pinegrass, blue grama, prairie junegrass, threadleaf sedge, and sun sedge.

Pathway 1.2A
Community 1.2 to 1.1

Tree growth in combination with periodic low intensity fire transitions the Young, Open Savanna community 1.2 to the Mature, Open Savanna community 1.1. Natural regrowth produces larger, older trees while periodic low intensity fire reduces stand density, permitting grasses and forbs to dominate the understory.

Pathway 1.3A
Community 1.3 to 1.2

Tree growth in combination with periodic low intensity fire transitions the Seedling/Shrub community 1.3 to the Young, Open Savanna community 1.2. Natural regrowth produces larger, older trees while periodic low intensity fire reduces stand density, permitting grasses and forbs to establish in the understory.

State 2
Fire Suppressed

The Fire Suppressed state occurs following long-term fire suppression efforts resulting in dense ponderosa pine communities accompanied by an understory component comprised primarily of shrubs. Herbaceous understory is greatly reduced. Forest health and wildfire conditions continue to deteriorate over the long term. The Fire Suppressed state results in an increase in litter quantity and a decline in litter quality due to a change in the understory composition.

Dominant plant species

ponderosa pine (Pinus ponderosa), tree
Rocky Mountain juniper (Juniperus scopulorum), tree
snowberry (Symphoricarpos), shrub

Community 2.1
Young, Dense Forest

This plant community is characterized by a dominance of young, dense ponderosa pine trees with diameters from 1 to 4 inches. Tree densities are very high. A variety of shrubs in a low growth form are common in this community phase including serviceberry, snowberry, chokecherry, skunkbush sumac, yucca, Rocky Mountain juniper, creeping juniper, and creeping barberry.

Community 2.2
Mature, Dense Forest

This plant community is characterized by a dominance of mature, dense ponderosa pine trees with a dominant overstory canopy. Rocky Mountain juniper and other shrubs comprise the lower canopy with a very sparse herbaceous composition in the understory.

Pathway 2.1A
Community 2.1 to 2.2

Tree growth in combination with long-term fire suppression transitions the Young, Dense Forest community 2.1 to the Mature, Dense Forest community 2.2. Natural growth produces larger, older trees while fire suppression permits small trees and shrubs to dominate the understory.

State 3
Mixed Grass

The Mixed Grass state occurs when the woody cover is removed by a high-intensity, stand-replacing fire and the site is dominated by a mixture of native herbaceous species. Exact timelines are unknown, but it is possible this state may persist for 50 to 100 years post-fire. The Mixed Grass state consists of one community.

Dominant plant species

bluebunch wheatgrass (Pseudoroegneria spicata), grass
little bluestem (Schizachyrium scoparium), grass

Community 3.1
Mixed Grass

This plant community is characterized by mid-statured bunchgrasses such as bluebunch wheatgrass, needle and thread, little bluestem, sideoats grama, and pinegrass. Shortgrasses and sedges such as blue grama, prairie Junegrass, threadleaf sedge, and sun sedge are present at low canopy cover. Ponderosa pine seedlings are rare or absent.

State 4
Shortgrass

The dynamics of the Shortgrass state are driven by long-term drought, improper grazing management such as continuous season-long or year-long grazing, or a combination of these factors. The Shortgrass state for this ecological site consists of one community.

Dominant plant species

blue grama (Bouteloua gracilis), grass

Community 4.1
Blue Grama and Sandberg Bluegrass

The plant community is characterized by a shortgrass dominated community comprised of blue grama and Sandberg bluegrass. Mid-statured grasses such as bluebunch wheatgrass, needle and thread, western wheatgrass, little bluestem, sideoats grama, and pinegrass are rare or absent. Ponderosa pine seedlings are rare or absent.

State 5
Invaded

The Invaded state occurs when invasive plant species invade native plant communities and displace the native species. The Invaded state consists of one community.

Dominant plant species

Kentucky bluegrass (Poa pratensis), grass
cheatgrass (Bromus tectorum), grass
field brome (Bromus arvensis), grass

Community 5.1
Invaded

Observations suggest that native species diversity declines significantly when invasive or noxious species exceed approximately 30 percent of the plant community. Non-native, perennial grasses such as Kentucky bluegrass, non-native, annual, invasive species such as cheatgrass and field brome, and noxious weed species can eventually dominate the seedbank of this site and displace native species. Reduced plant species diversity, simplified structural complexity, and altered ecological processes result in a state that is substantially departed from the Reference state.

Transition T1A
State 1 to 2

Long-term, intensive fire suppression transitions the Reference state to the Fire Suppressed state. Fire suppression permits stand density to increase and allows encroachment of shrubs and small trees into the understory.

Transition T1B
State 1 to 3

High-Intensity, stand replacing fire transitions the Reference state to the Mixed Grass state. High intensity fire results in the complete removal of the woody overstory and permits herbaceous species to dominate the site.

Restoration pathway R2A
State 2 to 1

A drastic change in management is necessary to restore the Fire Suppressed state to the Reference state. Intensive management inputs such as aggressive thinning and removal of many trees, harvesting, prescribed fire, and herbaceous weed control are necessary to reduce woody species density and restore the ecosystem processes of the Reference state. In addition, follow-up management is typically required in order to keep tree regeneration to a minimum and avoid a return to the Fire Suppressed state. This may include a combination of methods such as intensive grazing, prescribed fire, and brush management. These restoration methods are labor intensive, costly, and may not be a practical in all situations.

Conservation practices

Brush Management
Prescribed Burning
Prescribed Grazing
Herbaceous Weed Control

Transition T2A
State 2 to 3

High-Intensity, stand replacing fire transitions the Fire Suppressed state to the Mixed Grass state. High intensity fire results in the complete removal of the woody overstory and permits herbaceous species to dominate the site.

Transition T3C
State 3 to 1

Long-term tree regrowth and return to historic fire frequency/intensity transitions the Mixed Grass state back to the Reference state. Natural regeneration and growth of tree seedlings will occur over time and periodic low-intensity fire will permit development of an open ponderosa pine stand with a grass dominated understory.

Transition T3A
State 3 to 4

Prolonged drought, improper grazing management such as continuous season-long or year-long grazing, or a combination of these factors weaken the resilience of the Mixed Grass state and drive its transition to the Shortgrass state. The Mixed Grass state transitions to the Short-grass state when mid-statured graminoids become rare and shortgrasses such as blue grama and Sandberg bluegrass dominate the plant community.

Transition T3B
State 3 to 5

The Mixed Grass state transitions to the Invaded state when non-native grasses, noxious weeds, and other invasive plants invade the Mixed Grass state. Exotic plant species dominate the site in terms of cover and production and site resilience has been substantially reduced.

Restoration pathway R4A
State 4 to 3

Blue grama can resist displacement by other species. A reduction in livestock grazing pressure alone may not be sufficient to restore the Shortgrass state to the Mixed Grass state. Proper grazing management in combination with intensive management such as range planting and intensive weed management may be necessary. These restoration methods are labor intensive, costly, and may not be a practical in all situations.

Conservation practices

Prescribed Grazing

Additional community tables

Table 6. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 7. Community 1.2 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 8. Community 1.3 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 9. Community 2.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 10. Community 2.2 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 11. Community 3.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 12. Community 4.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Table 13. Community 5.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production ()	Foliar cover (%)

Supporting information

Inventory data references

Specific field data was not obtained for this provisional ecological site description. Existing field data were used in conjunction with a review of the scientific literature and professional experience to approximate the plant communities, states, and transitions. All community phases are considered provisional based on the sources identified in this ecological site description.

Other references

Anderson, R.C. 2006. Evolution and origin of the central grassland of North America: Climate, fire, and mammalian grazers. Journal of the Torrey Botanical Society 133:626-647.

Bloom-Cornelius, I.V. 2011. Vegetation response to fire and domestic and native ungulate herbivory in a Wyoming big sagebrush ecosystem. M.S. thesis, Oklahoma State University. Stillwater, OK.

Bragg, T.B. 1995. The physical environment of the Great Plains grasslands. In: A. Joern and K.H. Keeler (eds.) The Changing Prairie, Oxford University Press, Oxford, pp. 49–81.

Brown, P.M. and C.H. Sieg. 1999. Historical variability in fire at the ponderosa pine - Northern Great Plains prairie ecotone, southeastern Black Hills, South Dakota. Ecoscience 6:539-547

Cleland, D.T., et al. 1997. National hierarchical framework of ecological units. In: M.S. Boyce and A. Haney (eds.) Ecosystem Management Applications for Sustainable Forest and Wildlife Resources, Yale University Press, New Haven, CT.

Coupland, R.T. 1958. The effects of fluctuations in weather upon the grasslands of the Great Plains. Botanical Review 24:273-317.

Derner, J.D., and R.H. Hart. 2007. Grazing-induced modifications to peak standing crop in northern mixed-grass prairie. Rangeland Ecology and Management 60:270-276.

Dix, R.L. 1960. The effects of burning on the mulch structure and species composition of grasslands in western North Dakota. Ecology 41:49-56.

Federal Geographic Data Committee. 2008. The National Vegetation Classification Standard, Version 2. FGDC Vegetation Subcommittee. FGDC-STD-005-2008 (Version 2). pp. 126.

Fire Effects Information System. USDA Forest Service. http://www.fs.fed.us/database/feis/plants/shrub/amealn/all.html.

Hansen, P.L., et al. 1995. Classification and management of Montana's riparian and wetland sites. University of Montana, Montana Forest and Conservation Experiment Station, Miscellaneous Publication No. 54.

Harmoney, K.R. 2007. Grazing and burning Japanese brome (Bromus japonicus) on mixed grass rangelands. Rangeland Ecology and Management 60:479-486.

Hart, M., S.S. Waller, S.R. Lowry, and R.N. Gates. 1985. Disking and seeding effects on sod bound mixed prairie. Journal of Range Management 38:121-125.

Herrick, J.E., J.W. Van Zee, K.M. Havstad, L.M. Burkett, and W.G. Whitford. 2009. Monitoring manual for grassland, shrubland and savanna ecosystems. U.S. Department of Agriculture, Agricultural Research Service, Jornada Experimental Range, Las Cruces, NM.

Higgins, K.F. 1986. Interpretation and compendium of historical fire accounts in the Northern Great Plains. U.S. Fish and Wildlife Service Resource Publication 161.

lnteragency Ecological Site Handbook for Rangelands. USDA Natural Resources Conservation Service, USDA Forest Service, USDI Bureau of Land Management. January 2013.

Joern, A. 2005. Disturbance by fire frequency and bison grazing modulate grasshopper assemblages in tallgrass prairie. Ecology 86:861-873.

Kaye, M.W., C.A. Woodhouse, and S.T. Jackson. 2010. Persistence and expansion of ponderosa pine woodlands in the west-central Great Plains during the past two centuries. Journal of Biogeography 37:1668-1683.

Land Resource Regions and Major Land Resource Areas of the United States, the Caribbean, and the Pacific Basin. USDA Handbook 296. USDA Natural Resources Conservation Service. 2006.

Laycock, W.A. 1991. Stable states and thresholds of range condition on North American rangelands. Journal of Range Management 44:427-433.

Lockwood, J.A. 2004. Locust: The devastating rise and mysterious disappearance of the insect that shaped the American frontier. Basic Books, New York, NY.

McNab, W.H., et al. 2007. Description of ecological subregions: Sections of the conterminous United States [CD-ROM]. USDA Forest Service, General Technical Report WO-76B.

Montana State College. 1949. Similar vegetative rangeland types in Montana. Montana State College, Agricultural Experiment Station.

National Ecological Site Handbook. USDA Natural Resources Conservation Service. March 2017.

National Range and Pasture Handbook. USDA Natural Resources Conservation Service. December 2003.

National Soil Information System. USDA Natural Resources Conservation Service. https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/geo/?cid=nrcs142p2_053552.

National Soil Survey Handbook. USDA Natural Resources Conservation Service. November 2019.

Nesser, J.A., G.L. Ford, C.L. Maynard, and D.S. Page-Dumroese. 1997. Ecological units of the Northern Region: Subsections. USDA Forest Service, Intermountain Research Station, General Technical Report INT-GTR-369.

NRCS Plants Database. USDA Natural Resources Conservation Service. https://plants.usda.gov/java/.

Oard, M.J. 1993. A method of predicting chinook winds east of the Montana Rockies. Weather and Forecasting 8:166-180.

Pfister, R.D., et al. 1977. Forest Habitat Types of Montana, USDA-Forest Service, Technical Report No. INT-34.

Rowe, J.S. 1969. Lightning fires in Saskatchewan grassland. Canadian Field Naturalist 83:317-327.

Salo, E.D., et al. 2004. Grazing intensity effects on vegetation, livestock and non-game birds in North Dakota mixed-grass prairie. Proceedings of the 19th North American Prairie Conference, Madison, WI.

Samuel, M.J., and R.H. Hart. 1994. Sixty-one years of secondary succession on rangelands of the Wyoming High Plains. Journal of Range Management 47:184-191.

Soil Survey Manual. USDA Natural Resources Conservation Service. March 2017.

Soil Survey Staff. 2014. Keys to soil taxonomy, 12th edition. USDA Natural Resources Conservation Service.

Toledo, D., M. Sanderson, K. Spaeth, J. Hendrickson, and 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 7:543-552.

Umbanhowar, Jr., C.E. 2004. Interactions of climate and fire at two sites in the Northern Great Plains. Palaeogeography, Palaeoclimatology, and Palaeoecology 208:141-152.

U.S. Department of Agriculture, Natural Resources Conservation Service. Glossary of landform and geologic terms. National Soil Survey Handbook, Title 430-VI, Part 629.02c. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_054242 (accessed 13 April 2016).

U.S. Fish and Wildlife Service. 2013. Greater sage-grouse (Centrocercus urophasianus) conservation objectives: Final report.

Vermeire, L.T., J.L. Crowder, and D.B. Wester. 2011. Plant community and soil environment response to summer fire in the northern Great Plains. Rangeland Ecology and Management 64:37-46.

Vermeire, L.T., J.L. Crowder, and D.B. Wester. 2014. Semiarid rangeland is resilient to summer fire and postfire grazing utilization. Rangeland Ecology and Management 67:52-60.

Vuke, S.M., K.W. Porter, J.D. Lonn, and D.A. Lopez. 2007. Geologic map of Montana - information booklet: Montana Bureau of Mines and Geology Geologic Map 62-D.

Wambolt, C.L., K.S. Walhof, and M.R. Frisina. 2001. Recovery of big sagebrush communities after burning in south-western Montana. Journal of Environmental Management. 61:243-252.

Watts, M.J., and C.L. Wambolt. 1996. Long-term recovery of Wyoming big sagebrush after four treatments. Journal of Environmental Management 46:95-102.

Wilson, S.D., and J.M. Shay. 1990. Competition, fire, and nutrients in a mixed-grass prairie. Ecology 71:1959-1967.

Contributors

Jeff Fenton
Scott Brady
Maryjo Kimble
Brian Kloster

Approval

Kirt Walstad, 8/29/2024

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	09/05/2026
Approved by
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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Ecological site R058AY730MT

Ponderosa Pine 15-19

Last updated: 8/29/2024 Accessed: 09/05/2026

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Classification relationships

Ecological site concept

Associated sites

Similar sites

Table 1. Dominant plant species

Natural Resources
Conservation Service

Last updated: 8/29/2024
Accessed: 09/05/2026