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Ecological site R028AY215UT
Semidesert Gravelly Loam (Wyoming Big Sagebrush) North
Last updated: 5/02/2025
Accessed: 08/11/2026
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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): 028A–Ancient Lake Bonneville
MLRA 28A occurs in Utah (82 percent), Nevada (16 percent), and Idaho (2 percent). It encompasses approximately 36,775 square miles (95,246 square kilometers). A large area west and southwest of Great Salt Lake is a salty playa. This area is the farthest eastern extent of the Great Basin Section of the Basin and Range Province of the Intermontane Plateaus. It is an area of nearly level basins between widely separated mountain ranges trending north to south. The basins are bordered by long, gently sloping alluvial fans. The mountains are uplifted fault blocks with steep side slopes. Most of the valleys are closed basins containing sinks or playa lakes. Elevation ranges from 3,950 to 6,560 feet (1,204 to 2,000 meters) in the basins and from 6,560 to 11,150 feet (1,996 to 3,398 meters) in the mountains. Much of the MLRA has alluvial valley fill and playa lakebed deposits at the surface from pluvial Lake Bonneville, which dominated this MLRA 13,000 years ago. A level line of remnant lake terraces on some mountain slopes indicates the former extent of this glacial lake. The Great Salt Lake is what remains of the pluvial lake.
Mountains in the interior of this MLRA consist of tilted blocks of marine sediments from Cambrian to Mississippian age with scattered outcrops of Tertiary continental sediments and volcanic rocks. The average annual precipitation is 5 to 12 inches (13 to 30 cm) in the valleys and ranges up to 49 inches (124 cm) in the mountains. Most of the rainfall in the southern LRU occurs as high-intensity, convective thunderstorms during the growing season (April through September). The driest period is from midsummer to early autumn in the northern LRU. Precipitation in winter typically occurs as snow. The average annual temperature is 39 to 53 °F (4 to 12 °C). The freeze-free period averages 165 days and ranges from 110 to 215 days, decreasing in length with increasing elevation. The dominant soil orders in this MLRA are Aridisols, Entisols, and Mollisols. Soils are dominantly in the mesic or frigid soil temperature regime, aridic or xeric soil moisture regime, and mixed mineralogy. The soils are generally well drained, loamy or loamy-skeletal, and very deep.LRU notes
The Basin and Range North LRU exhibits dry summer with stronger xeric patterns than the Basin and Range South LRU. Ranges in the north LRU are about 50 percent Paleozoic sedimentary/metasedimentary (limestone/quartzite dominant) and about 10 percent Tertiary volcanics. The basin floors are between 4,200 and 5,100 feet (1,280 to 1,554 meters) in elevation. Pinyon and juniper sites have a greater percentage of Utah juniper (Juniperus osteosperma) in the plant community than pinyon pine (Pinus edulis or monophylla). The Basin and Range North have few semidesert ecological sites with Utah juniper. Cool season grasses, such as bluebunch wheatgrass (Pseudoroegneria spicata), are dominant in the plant community, while warm season grasses are largely absent or a small component of the plant community.
Classification relationships
MLRA: 28A, Great Salt Lake Area LRU Basin and Range North Ecological Zone Semidesert Semidesert Gravelly Loam (Wyoming big sagebrush)
EPA Ecoregions: North American Deserts Cold Deserts Central Basin and Range Shadscale-Dominated Saline Basins, Sagebrush Basins and Slopes, Woodland- and Shrub-Covered Low MountainsEcological site concept
The Semidesert Gravelly Loam (Wyoming Big Sagebrush) North site is typically found between 4,400 and 6,500 feet on fan terraces, fan remnants, and alluvial fans on slopes less than 15 percent. The Reference State, Community Phase 1.1, is typically dominated by Wyoming big sagebrush and bluebunch wheatgrass. The Reference State can cycle between two other dominant plant community phases. Community Phase 1.2 occurs soon after fire, with rabbitbrush and perennial bunch grasses as the dominant plants. Community Phase 1.3 develops in the absence of fire, with Wyoming big sagebrush cover increasing and reduced herbaceous cover.
Associated sites
R028AY257UT Semidesert Steep Gravelly Loam (Wyoming Big Sagebrush)
This site occurs on steep slopes.
R028AY220UT Semidesert Loam (Wyoming Big Sagebrush)
This site will occur where the soil does not have as much influence from rock fragments and it often found in association with site R028AY215UT.
R028AY006UT Loamy Bottom (basin wildrye)
This site may be located down slope in concave areas where run-in water accumulates.
R028AY223UT Semidesert Sand (Utah Juniper)
This site occurs where sand has been deposited.
R028AY227UT Semidesert Gravelly Sandy Loam (Black Sagebrush) North
This site occurs on alluvial fans on lake terraces on dep gravelly sandy loam soils. It is dominated by black sagebrush.
R028AY234UT Semidesert Shallow Loam (Utah juniper-Salina wildrye)
This site occurs on mountainsides and hillside in shallow soil. It is dominated by Utah juniper and salina wildrye.
R028AY238UT Semidesert Shallow Loam (Utah Juniper-Bluebunch Wheatgrass) North
This site is found upslope on steep mountainsides and hillsides on shallow soils. It is dominated by Utah juniper and bluebunch wheatgrass.
R028AY252UT Semidesert Stony Loam (Black Sagebrush)
This site has more rock fragments in the soil profile and is dominated by black sagebrush.
Similar sites
R028AY028NV DROUGHTY LOAM 8-10 P.Z.
This site is similar in soil and plant characteristics that has been developed for Nevada.
R028AF214UT Semidesert Gravelly Loam (Wyoming Big Sagebrush) South
This site similar but occurs in the southern Basin and Range LRU and will have more influence from summer convective storms and will have a component of warm season grasses in the community.
R028AY220UT Semidesert Loam (Wyoming Big Sagebrush)
This site does not have a gravelly soil and it often found in association with site R028AY215UT.
R028AY257UT Semidesert Steep Gravelly Loam (Wyoming Big Sagebrush)
This site occurs on steep slopes.
Table 1. Dominant plant species
Tree Not specified
Shrub (1) Artemisia tridentata subsp. wyomingensis
Herbaceous (1) Pseudoroegneria spicata
Physiographic features
The Semidesert Gravelly Loam (Wyoming Big Sagebrush) North site is typically found between 4,400 and 6,500 feet on fan terraces, fan remnants, and alluvial fans. The slope is typically between 2 and 15 percent. There is no flooding or ponding on this site and the runoff is very low to low.
As the site continues downslope, its occurrence ends when it meets the basin floor. The upslope occurrence ends when the fans end and meet the hill landform (see Block Diagram 1A).
Figure 2. Block Diagram 1A
Table 2. Representative physiographic features
Landforms (1) Fan remnant
(2) Terrace
(3) Alluvial fan
Flooding frequency None Ponding frequency None Elevation 4400 – 6000 ft Slope 2 – 15 % Aspect Aspect is not a significant factor Climatic features
The climate is semi-arid and characterized by cold snowy winters and warm dry summers. The average annual precipitation is 10 to 14 inches. Approximately 70 percent comes as rain from March through October. On average, June through September are the driest months and March through May are the wettest months. The freeze-free period averages 159 days and ranges from 148 to 170 days.
Table 3 Representative climatic features
Frost-free period (characteristic range) 80-110 days Freeze-free period (characteristic range) 110-140 days Precipitation total (characteristic range) 10-10 in Frost-free period (actual range) 60-110 days Freeze-free period (actual range) 110-150 days Precipitation total (actual range) 10-10 in Frost-free period (average) 90 days Freeze-free period (average) 130 days Precipitation total (average) 10 in Characteristic rangeActual rangeBarLineFigure 3. Monthly precipitation range
Characteristic rangeActual rangeBarLineFigure 4. Monthly minimum temperature range
Characteristic rangeActual rangeBarLineFigure 5. Monthly maximum temperature range
BarLineFigure 6. Monthly average minimum and maximum temperature
Figure 7. Annual precipitation pattern
Figure 8 Annual average temperature pattern
Climate stations used
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(1) OAK CITY [USC00426357], Delta, UT
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(2) SIGURD U P & L [USC00427800], Richfield, UT
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(3) ELBERTA [USC00422418], Cedar Valley, UT
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(4) GROUSE CREEK [USC00423486], Grouse Creek, UT
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(5) VERNON [USC00429133], Vernon, UT
">Influencing water features
The Semidesert Gravelly Loam (Wyoming Big Sagebrush) North site is not directly influenced by any water features.
Soil features
The soils were formed in mixed alluvium and are well to somewhat excessively drained. The soils are deep with typically over 15 percent gravels the surface and subsurface. These soils typically have a layer of carbonate accumulation above 20 inches. The main limiting soil factor that influences plant growth are high percentage of rock fragments and the zone of carbonate accumulation. The soil moisture regime is xeric and the soil temperature is mesic.
The Semidesert Gravelly Loam (Wyoming big sagebrush) North has been used in the following soil surveys and has been correlated to the following components:
NV779-Hiko Peak
UT601-Collard Acana, Brobett, Hiko Peak, Darkbull, Sitar
UT602-Sanpete
UT608-Hiko Peak, Orcky, Sanpete
UT611-Hiko Peak
UT617-Hiko Peak*, Sanpete*
UT618-Escalante, Hiko Peak, Pober
UT627 and 628-Torrifluvents, Thorriorthents
UT636-Broncho*
*these components need to be evaluated to be re-correlated to the southern LRU site, R028AF214UTTable 4. Representative soil features
Parent material (1) Alluvium – limestone, sandstone, and shale
Surface texture (1) Gravelly loam
(2) Stony sandy loam
Family particle size (1) Loamy
Drainage class Well drained to somewhat excessively drained Permeability class Moderate to moderately rapid Soil depth 60 in Surface fragment cover <=3" 11 – 28 % Surface fragment cover >3" 0 – 3 % Available water capacity
(0-40in)3.1 – 4.4 in Calcium carbonate equivalent
(0-40in)1 – 30 % Electrical conductivity
(0-40in)0 – 2 mmhos/cm Sodium adsorption ratio
(0-40in)0 – 13 Soil reaction (1:1 water)
(0-40in)7.9 – 9 Subsurface fragment volume <=3"
(Depth not specified)32 – 36 % Subsurface fragment volume >3"
(Depth not specified)0 – 12 % Ecological dynamics
The Reference State is typically dominated by Wyoming big sagebrush and bluebunch wheatgrass. This site would cycle between three dominant plant community phases. One community phase would occur soon after a fire, with rabbitbrush and the perennial bunch grasses as the dominant plants and another community would develop in the absence of fire, with Wyoming big sagebrush cover increasing and reduced herbaceous cover.
The introduction of non-native species alters the trajectory of this site. Non-native species, such as cheatgrass and annual forbs, increase fine fuels and fire frequency. Once annuals become dominant, fire frequency continues to promote the invasive annual state.
This site has been successfully seeded to non-native bunchgrasses, reducing the fire return interval and allowing native shrubs to return to the system.State and transition model
Custom diagramStandard diagram
Figure 9. R028AY215UT 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 textEcosystem states
State 3 submodel, plant communities
State 4 submodel, plant communities
State 5 submodel, plant communities
State 6 submodel, plant communities
State 1
Reference StateThe Reference State includes plant communities dominated by a diverse mixture of perennial grasses, Wyoming big sagebrush, and yellow rabbitbrush. These community phases occur depending on length time since a disturbance (fire, insects, drought, or over browsing) that removes Wyoming big sagebrush from the community. Adequate duration, timing, and intensity of grazing is required to maintain plant vigor and health of the plant community. Plant communities in the Reference State will consist of only native species.
Community 1.1
Wyoming big sagebrush, bluebunch wheatgrass, Indian ricegrass, Squirreltail, other perennial grassesCommunity Phase 1.1 is dominated by Wyoming big sagebrush and bluebunch wheatgrass. Shadscale and winterfat are also commonly present in the shrub layer. Bluebunch wheatgrass and Indian ricegrass are the principle perennial grasses. Bottlebrush squirreltail is commonly present. Forbs include carpet phlox and scarlet globemallow. Percent composition by air-dry weight is 45 percent grass, 10 percent forbs, and 45 percent shrubs. Natural fire frequency is estimated to be 100 years.
Figure 10. 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 203 349 450 Shrub/Vine 300 349 400 Forb 45 78 150 Total 548 776 1000 Table 6. Ground cover
Tree foliar cover 0% Shrub/vine/liana foliar cover 20-30% Grass/grasslike foliar cover 20-30% Forb foliar cover 0-10% Non-vascular plants 0% Biological crusts 0% Litter 0% Surface fragments >0.25" and <=3" 0% Surface fragments >3" 0% Bedrock 0% Water 0% Bare ground 0% Table 7. Canopy structure (% cover)
Height Above Ground (ft) Tree Shrub/Vine Grass/
GrasslikeForb <0.5 – – – – >0.5 <= 1 – – – – >1 <= 2 – – 25-35% 0-10% >2 <= 4.5 – 15-25% – – >4.5 <= 13 – – – – >13 <= 40 – – – – >40 <= 80 – – – – >80 <= 120 – – – – >120 – – – – Figure 11. Plant community growth curve (percent production by month). UT2151 , PNC. Excellent Condition.
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 5 15 40 30 5 5 0 0 0 0 Community 1.2
Bluebunch wheatgrass, Indian ricegrass, squirreltailNative perennial bunchgrasses dominate this post-fire community phase. Wyoming big sagebrush and shadscale decrease in the community. Winterfat has the ability to resprout and re-establish following a fire. Yellow rabbitbrush and horsebrush species (Nuttall, smooth and/or spiny) may increase significantly following fire. Fire tolerant shrubs typically persist as dominants in the community for 100 years or longer. Bluebunch wheatgrass and other cool season bunchgrasses flourish.
Community 1.3
Wyoming big sagebrushWyoming big sagebrush and shadscale increases significantly. Winterfat and yellow rabbitbrush may increase also. Shrubs become decadent due to age. Bluebunch wheatgrass, Indian ricegrass and other cool season bunchgrasses begin to lose vigor because of increased shrub competition and become dense with old vegetation. Western wheatgrass increases in herbaceous cover. Percent composition by air-dry weight is 30 percent grass, 10 percent forbs, and 60 percent shrubs.
Pathway 1.1b
Community 1.1 to 1.2Recent fire occurrence, lightning or human caused (1 to 30 years). Site is properly grazed.
Pathway 1.1a
Community 1.1 to 1.3Extended period of time without a major disturbance such as fire; insect damage; or prolonged drought. Fire frequency extends well beyond the 100 year average for the site.
Pathway 1.2a
Community 1.2 to 1.1Normal fire frequency of 40 to 50 years returns on the site.
Pathway 1.3a
Community 1.3 to 1.2Recent fire occurrence (1 to 30 years).
State 2
Current Potential State
The Current Potential State includes plant communities dominated by a diverse mixture of perennial grasses, a mixture of Wyoming big sagebrush, and perennial grasses, and a community dominated by Wyoming big sagebrush. These community phases occur depending on the time since a disturbance that kills Wyoming big sagebrush has occurred, such as fire, insects, or drought, and grazing that provides adequate duration, timing, and intensity that maintain plant vigor and health of the plant community.
Plant communities in this state can include native, acclimatized, naturalized, and invasive non-native species. The Current Potential State is irreversibly changed from the Reference State because the non-native species remain a permanent part of the community.
This plant community has the composition, structure and cover present that facilitates infiltration, nutrients are being cycled through deep rooted perennial grasses, forbs, and evergreen shrubs, and cool season energy capture throughout the entire growing season (March to October, when soil moisture is available) such that this plant community and site resiliency is maintained. With a lengthened fire return interval (greater than 60 years), an increase in sagebrush canopy occurs until sagebrush dominates resource use. This results in a decrease in vigor, cover and reproduction of perennial grasses, and may result in an increase of invasive annuals such as cheatgrass. This leads into transition T2b. With increased sagebrush cover, bare ground increases, infiltration decreases, and a reduction in the amount of nutrient cycling and energy capture.Community 2.1
Wyoming big sagebrush, bluebunch wheatgrass, Indian ricegrass
Figure 12. Ground cover photo
Community Phase 2.1 is dominated by Wyoming big sagebrush. Shadscale and winterfat are also commonly present in the shrub layer. Bluebunch wheatgrass and Indian ricegrass are the principle perennial grasses. Bottlebrush squirreltail may also be present. Forbs include carpet phlox and scarlet globemallow. The community is dominated by native species, but may include acclimatized, naturalized and invasive non-native species. Percent composition by air-dry weight is 45 percent grass, 10 percent forbs, and 45 percent shrubs. Natural fire frequency is estimated to be 100 years.
Community 2.2
Bluebunch wheatgrass, Indian ricegrass
Figure 13. Bluebunch wheatgrass dominated phase
Wyoming big sagebrush and shadscale decrease in the community. Winterfat resprouts following the fire. Yellow rabbitbrush and horsebrush species (Nuttall, smooth and/or spiny) may increase significantly in the community following fire. Several native grasses dominate the understory. Fire tolerant shrubs typically persist as dominants in the community for 30 years or longer. This community is dominated by native species, but may include acclimatized, naturalized, and invasive non-native species.
Community 2.3
Wyoming big sagebrush
Figure 14. Wyoming big sagebrush dominated
Figure 15. Site located in Ibapah, UT before a harrow treatment
Figure 16. Wyoming sagebrush dominated with some Utah juniper
Figure 17. Some juniper encroachment on the site
Figure 18. Low grass cover
Figure 19. More juniper encroachment
Wyoming big sagebrush and shadscale increase in percent composition. Winterfat and Yellow rabbitbrush may increase also. Shrubs become decadent due to age. Bluebunch wheatgrass, Indian ricegrass and other cool season bunchgrasses begin to lose vigor because of improper grazing (including, season long overstocking, wrong season, etc.) and/or increased shrub competition and become dense with old vegetation. This community is dominated by native species, but may include acclimatized, naturalized, and invasive non-native species. Utah Juniper can encroach in this community phase but is small and low in cover. Percent composition by air-dry weight is 30 percent grass, 10 percent forbs, and 60 percent shrubs.
Community 2.4
Wyoming big sagebrush, native grasses, invasive annual grasses
Sagebrush is increasing in dominance and capturing site resources, reducing opportunity for perennial bunchgrasses to thrive. Fire frequency extends beyond the 100 year average for the site. A few Utah juniper may invade the site if a seed source is available in the upper precipitation ranges (10 to 12 inches).
An increase in sagebrush canopy until sagebrush dominates resource use, resulting in a decrease in vigor, cover and reproduction of perennial bunch grasses, and near co-dominance with invasive annuals such as cheatgrass. This community phase is at risk of transition to another state.Pathway 2.1b
Community 2.1 to 2.2
Wyoming big sagebrush, bluebunch wheatgrass, Indian ricegrass
Bluebunch wheatgrass, Indian ricegrassFire removes non-sprouting shrubs from the community. Yellow rabbitbrush and/or horsebrush species become dominant. Recent fire occurrence (1 to 30 years).
Pathway 2.1a
Community 2.1 to 2.3
Wyoming big sagebrush, bluebunch wheatgrass, Indian ricegrass
Wyoming big sagebrushImproper grazing (including season long, overstocking, wrong season, etc.) and/or drought remove annual and perennial fine fuels from the site lessening the potential for fire to occur. Fire frequency extends beyond the 40 to 50 year average for the site. Utah juniper may invade the site if a seed source is available and typically only in drainages.
Pathway 2.1c
Community 2.1 to 2.4
Wyoming big sagebrush, bluebunch wheatgrass, Indian ricegrass
Wyoming big sagebrush, native grasses, invasive annual grassesImproper grazing (including season long, overstocking, continual spring grazing, etc.) and/or drought remove perennial grass facilitating an increase in invasive annual species.
Pathway 2.2a
Community 2.2 to 2.1
Bluebunch wheatgrass, Indian ricegrass
Wyoming big sagebrush, bluebunch wheatgrass, Indian ricegrassSite is properly grazed for an extended period of time. Native perennial vegetation is recovering. Fire frequency returns to within the normal range for the state. 100 years or more without a fire occurrence (normal fire frequency).
Pathway 2.3a
Community 2.3 to 2.2
Wyoming big sagebrush
Bluebunch wheatgrass, Indian ricegrassFire removes non-sprouting shrubs from the community. Yellow rabbitbrush and/or horsebrush species become dominant. Recent fire occurrence (1 to 30 years).
Pathway 2.3b
Community 2.3 to 2.4
Wyoming big sagebrush
Wyoming big sagebrush, native grasses, invasive annual grassesContinued lack of fire or other disturbance to reduce sagebrush cover. Continued grazing pressure on native bunch grasses.
State 3
Native Shrub/Invasive Annual State
Native shrubs such as Wyoming big sagebrush or rabbitbrush dominate the site. The dominance depends on time since fire. Wyoming big sagebrush is non-sprouting and will be killed by fire. Rabbitbrush can sprout after a fire and can become the dominant shrub. The Native Shrub/Invasive Annual State typically has invasive grasses and/or forbs as the dominant understory species. There may be a few native species remaining, but they do not dominate the plant community. Utah junipers may increase to occupy a significant portion of the over story, if a seed source is present. Wyoming big sagebrush dominates the shrub layer and may be decadent due to age. Bluebunch wheatgrass and other native bunchgrasses are significantly reduced due to increased shrub competition and/or heavy grazing pressure. Invasive annuals such as cheatgrass, annual mustards, and redstem storksbill dominate the understory. The occurrence of fire extends well beyond the normal period for the site.
Community 3.1
Wyoming big sagebrush and/or Utah juniper, invasive annuals
Figure 20. Wyoming sagebrush dominated phase
Figure 21. Utah juniper encroachment
Figure 22. Wyoming big sagebrush and cheatgrass dominated pha
Figure 23. Wyoming big sagebrush and cheatgrass dominated pha
Figure 24. Wyoming big sagebrush dominated phase
Figure 25. Unburned Oak City watershed
Figure 26. Unburned Oak City watershed
Wyoming sagebrush is typically the dominant shrub in this community phase. Where Utah juniper has invaded, Wyoming big sagebrush and other shrubs decline, otherwise they dominate the community. Winterfat is dead or dying. Remaining perennial herbaceous vegetation is mostly found only in protected locations under shrubs. Invasive, non-native grasses and weeds including cheatgrass, annual mustards, redstem storksbill, etc. dominate the understory.
State 4
Invasive Annual State
Invasive grasses and forbs dominate the Invasive Annual State. This may occur under a shortened fire return interval which excludes native shrubs by frequent burning or this may occur with repeated improper grazing, or a combination of the two. Bluebunch wheatgrass and other native bunchgrasses are significantly reduced due to increased shrub competition and/or heavy grazing pressure. Only remnant perennial species remain. Highly combustible fine fuels from invasive annuals to dominate the community. Fire is common. Fire frequency is 10 to 30 years.
Community 4.1
Invasive annuals
Figure 27. Broom snakeweed dominated after a fire.
Figure 28. Invasive annual dominated phase.
Figure 29. Invasive annuals dominated phase.
Figure 30. Invasive annuals and broom snakeweed dominated site.
Figure 31. Cheatgrass and redstem storks bill dominated site.
Figure 32. Invasive annual forbs and grasses dominated site.
Invasive annuals dominate this community phase. If shrubs are present, yellow rabbitbrush dominates the shrub layer. Remaining winterfat is mostly dead. Horsebrush species (Nuttall, smooth, and spiny) can also be plentiful if conditions are right. Fire tolerant shrubs may persist as dominants with fire periods reoccurring at intervals of 5 to 30 years. Broom snakeweed may be a dominant episodic species when conditions are favorable. Only remnant perennial bunchgrasses remain, if any; invasive annuals including cheatgrass, annual mustards, redstem storksbill, etc. dominate the understory.
State 5
Seeded Range State
The Seeded Range State is seeded to rangeland species that are composed of mostly introduced species. Unwanted trees and/or shrubs are reduced but they may occupy a portion of the site through natural regeneration. Invasive annual grasses and weedy forb species primarily, cheatgrass and various annual mustards, may be present in the seeding, but do not dominate.
Community 5.1
Introduced perennial grasses
Figure 33. Crested wheatgrass seeded site
This community is seeded to rangeland species that is composed of mostly introduced species. Unwanted trees and/or shrubs are reduced but they may occupy a portion of the site through natural regeneration. Invasive annual grasses and weedy forb species primarily, cheatgrass and various annual mustards, may be present in the seeding, but do not dominate. Range seedings, when healthy, are usually resistant to fire.
Community 5.2
Wyoming big sagebrush, introduced perennial grasses
Figure 34. Wyoming big sagebrush and introduced perennial gra
Figure 35. Ground cover photo of phase
Figure 36. Mature Wyoming big sagebrush dominated site with i
This community includes the dominance of introduced perennial understory. Native shrubs are re-establishing.
Pathway 5.1a
Community 5.1 to 5.2
Introduced perennial grasses
Wyoming big sagebrush, introduced perennial grassesSeeding is not well established; continued improper grazing (including season long, overstocking, wrong season, etc.); and/or drought reduces any perennial grasses established. Highly combustible fine fuels from invasive annuals shorten the fire frequency.
Pathway 5.2a
Community 5.2 to 5.1
Wyoming big sagebrush, introduced perennial grasses
Introduced perennial grassesSite receives good grazing management. Mechanical, chemical, biological or fire disturbances reduce the woody vegetation components of the community. Perennial herbaceous vegetation very slowly recovers.
State 6
Novel Grassland State
The Novel Grassland State is co-dominated by perennial natives Aristida purpurea and Sporobolus cryptandrus, and the non-native annual Bromus tectorum. Aristida purpurea and Sporobolus cryptandrus are warm season bunch grasses that occupy very small components of the historic plant community, but for reasons not yet know, are the dominant perennial grasses in this state.
Community 6.1
Native/Invasive Grassland
Figure 37. Tooele County, Utah
Figure 38. Tooele County, Utah
The Native/Invasive Grassland Threeawn / Cheatgrass co-dominated plant community is co-dominated by perennial natives Aristida purpurea and Sporobolus cryptandrus, both warm season bunch grasses that occupy very small components of the historic plant community, and Bromus tectorum.
Transition T1a
State 1 to 2The threshold is crossed when there is an introduction of non-native species, primarily cheatgrass and various annual mustards, that become established in the community.
Transition T2a
State 2 to 3
Current Potential State
Native Shrub/Invasive Annual StateSustained, long-term improper grazing (including season long, overstocking, wrong season, etc.); and/or prolonged drought. Lengthening of the fire return interval.
Transition T2b
State 2 to 4
Current Potential State
Invasive Annual StateLong-term improper grazing (including season long, overstocking, wrong season, etc.) and/or prolonged drought; shortened fire return interval.
Transition T3a
State 3 to 4
Native Shrub/Invasive Annual State
Invasive Annual StateLong-term improper grazing (including season long, overstocking, wrong season, etc.) and/or prolonged drought; shortened fire frequency.
Transition T3b
State 3 to 5
Native Shrub/Invasive Annual State
Seeded Range StateSeeding of mostly introduced species.
Transition T4a
State 4 to 5
Invasive Annual State
Seeded Range StateSeeding of mostly introduced species.
Transition T4b
State 4 to 6
Invasive Annual State
Novel Grassland StateThe mechanism for this transition is unknown. Some studies suggest that intense grazing may cause the shift in the plant community.
Transition T5a
State 5 to 3
Seeded Range State
Native Shrub/Invasive Annual StateLong-term improper grazing (including season long, overstocking, wrong season, etc.) and/or prolonged drought; lengthened fire frequency.
Transition T5b
State 5 to 4
Seeded Range State
Invasive Annual StateLong-term improper grazing (including season long, overstocking, wrong season, etc.) and/or prolonged drought; shortened fire return interval allows the vegetation on the site to be dominated by invasive annuals.
Additional community tables
Table 8. Community 1.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Shrub/Vine0 Primary Shrubs 224–360 Wyoming big sagebrush ARTRW8 Artemisia tridentata ssp. wyomingensis 160–240 – shadscale saltbush ATCO Atriplex confertifolia 40–80 – yellow rabbitbrush CHVI8 Chrysothamnus viscidiflorus 24–40 – 3 Secondary Shrubs 56–80 black sagebrush ARNO4 Artemisia nova 8–24 – spiny hopsage GRSP Grayia spinosa 8–24 – broom snakeweed GUSA2 Gutierrezia sarothrae 8–24 – winterfat KRLA2 Krascheninnikovia lanata 8–24 – bud sagebrush PIDE4 Picrothamnus desertorum 8–24 – Nuttall's horsebrush TENU2 Tetradymia nuttallii 8–24 – plains pricklypear OPPO Opuntia polyacantha 8–24 – Grass/Grasslike0 Primary Grasses 224–360 bluebunch wheatgrass PSSP6 Pseudoroegneria spicata 160–240 – Indian ricegrass ACHY Achnatherum hymenoides 40–80 – squirreltail ELEL5 Elymus elymoides 24–40 – 1 Secondary Grasses 40–80 Grass, perennial 2GP Grass, perennial 8–24 – needle and thread HECO26 Hesperostipa comata 8–24 – western wheatgrass PASM Pascopyrum smithii 8–24 – Sandberg bluegrass POSE Poa secunda 8–24 – sand dropseed SPCR Sporobolus cryptandrus 0–24 – Forb2 Forbs 56–80 Forb, annual 2FA Forb, annual 0–50 – Forb, perennial 2FP Forb, perennial 0–50 – Holboell's rockcress ARHO2 Arabis holboellii 8–24 – roundspike cryptantha CRHU2 Cryptantha humilis 8–24 – cushion buckwheat EROV Eriogonum ovalifolium 8–24 – granite prickly phlox LIPU11 Linanthus pungens 8–24 – spiny phlox PHHO Phlox hoodii 8–24 – scarlet globemallow SPCO Sphaeralcea coccinea 8–24 – Pacific aster SYCHC Symphyotrichum chilense var. chilense 8–24 – Table 9. Community 1.2 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 10. Community 1.3 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 11. Community 2.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 12. Community 2.2 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 13. Community 2.3 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 14. Community 2.4 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 15. Community 3.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 16. Community 4.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 17. Community 5.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 18. Community 5.2 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 19. Community 6.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Interpretations
Animal community
The Semidesert Gravelly Loam (Wyoming Big Sagebrush) North site is suited for grazing by cattle and sheep during fall, winter, and spring.
Wildlife using this site include rabbit, coyote, fox, badger, pronghorn antelope, mule deer, and dove.
This is a short list of the more common species found. Many other species are present as well and migratory birds are present at times.Hydrological functions
The soils are in hydrologic group B with runoff curves ranging from 61 to 79 depending on hydrologic condition.
Recreational uses
Resources that have special aesthetic and landscape values are wildflowers. Some recreation uses of this site are hiking and hunting.
Wood products
None
Other information
Threatened and endangered species include plants and animals.
Supporting information
Inventory data references
NW ¼ of NW ¼ Section 22, Township 9N, Range 11W; SW ¼ of SW ¼ Section 24, Township 9N, Range 19W.
Type locality
Location 1: Box Elder County, UT Township/Range/Section T9N R11W S22 General legal description NW 1/4 of NW 1/4 Location 2: Box Elder County, UT Township/Range/Section T9N R19W S24 General legal description SW 1/4 of SW 1/4 Other references
Utah Division of Wildlife Resources, Range Trend Data, Kelton, UT.
Rogers, G. 1982. Then and Now: A photographic history of vegetation change in the central Great Basin Desert. University of Utah Press, SLC, 179 p.Contributors
David J. Somorville
Keith Wadman, Shane Green
Sarah QuistbergApproval
Jamin Johanson, 5/02/2025
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) Jack Alexander, Range Specialist, Synergy Resource Solutions, Inc. Julia Kluck, Soil Scientist, Synergy Resource Solutions, Inc. Shane Green, State Range Specialist, Utah NRCS Jamison Jewkes, Range Specialist, Utah NRCS Contact for lead author Shane Green, Shane.Green@ut.usda.gov Date 02/08/2010 Approved by Approval date Composition (Indicators 10 and 12) based on Annual Production Indicators
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Number and extent of rills:
No rills present. Very minor rill development may occur in sparsely vegetated areas. If rills are present, they should be widely spaced and not connected. Rill development may increase following large storm events, but should begin to heal during the following growing season. Frost heaving will accelerate recovery. Rill development may increase when run inflow enters site from adjacent sites that produce large amounts of runoff (i.e. steeper sites, slickrock, rock outcrop). Site is essentially level and rills typically do not form. -
Presence of water flow patterns:
Water flow patterns will be short (2-5’), narrow (<1’), and meandering; interrupted by plants and exposed rocks. Slight to no evidence of erosion or deposition associated with flow patterns. -
Number and height of erosional pedestals or terracettes:
Plants may have small pedestals where they are adjacent to water flow patterns, but without exposed roots. Terracettes should be few and stable. Terracettes should be small (1-2”) and show little sign of active erosion. Some plants may appear to have a pedestal but rather than be formed by erosion, the only place litter accumulates and soil collects is at plant bases forming the appearance of a pedestal. Well-developed biological crusts may appear pedestalled, but are actually a characteristic of the crust formation. Some plants may appear to have a pedestal but rather than be formed by erosion, the only place litter accumulates and soil collects is at plant bases forming the appearance of a pedestal. -
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
20-35% bare ground (soil with no protection from raindrop impact). Herbaceous communities are most likely to have lower values. As species composition by shrubs increases, bare ground is likely to increase. Poorly developed biological soil crust that is susceptible to raindrop splash erosion should be recorded as bare ground. Very few if any bare spaces of greater than 1 square foot. -
Number of gullies and erosion associated with gullies:
No gullies present. -
Extent of wind scoured, blowouts and/or depositional areas:
Very minor evidence of active wind-generated soil movement. Wind scoured (blowouts) and depositional areas are rarely present. If present they have muted features and are mostly stabilized with vegetation and/or biological crust. Gravel or desert pavement protects the site from wind scour. -
Amount of litter movement (describe size and distance expected to travel):
Most litter resides in place with some redistribution caused by water and wind movement. Very minor litter removal may occur in flow patterns and rills with deposition occurring at points of obstruction. The majority of litter accumulates at the base of plants. Some leaves, stems, and small twigs may accumulate in soil depressions adjacent to plants. Woody stems are not likely to move. -
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil surface is moderately stable (average soil stability score of 3.5 -5). Litter, rock, and biological crusts all contribute to the surface soil resistance to erosion. -
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
This description is based on the modal soil (Hiko Peak GR-L, soil survey area: 611, Tooele). This site has 3 correlated soils, resulting in variation of each of these attributes. Unless working on a location with the modal soil, it is critical to supplement this description with the soil-specific information from the published soil survey. Soil surface horizon is typically 2 to 6 inches deep. Structure is typically weak thin platy. Color is typically brownish gray (10YR 6/2), dark brown (10YR 3/3) moist. An ochric horizon extends to a depth of 6 inches. An ochric horizon typically extends to a depth of 2 to 10 inches. The ochric horizon is a surface horizon lacking fine stratification and which is either light colored, or thin, or has an low organic carbon content, or is massive and (very) hard when dry. The A horizon would be expected to be more strongly developed under plant canopies. It is important if you are sampling to observe the A horizon under plant canopies as well as the interspaces. -
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
Bunchgrasses and shrubs equally important for increasing infiltration and reducing runoff. Litter plays a role in increasing infiltration and decreasing runoff. Plants provide microhabitat for seedlings, catch litter and soil, and slow raindrops and runoff. Vascular plants and/or well-developed biological soil crusts (where present) will break raindrop impact and splash erosion. Spatial distribution of vascular plants and interspaces between well-developed biological soil crusts (where present) provide detention storage and surface roughness that slows runoff allowing time for infiltration. Interspaces between plants and any well-developed biological soil crusts (where present) may serve as water flow patterns during episodic runoff events, with natural erosion expected in severe storms. When perennial grasses decrease, reducing ground cover and increasing bare ground, runoff is expected to increase and any associated infiltration reduced. Shrubs catch snow, slow wind evaporation, and provide microhabitat for seedling establishment. -
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
None. Naturally occurring soil horizons may be harder than the surface because of an accumulation of calcium carbonate and should not be considered as compaction layers. -
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:
Bluebunch wheatgrass, Wyoming big sagebrushSub-dominant:
Indian ricegrass, Shadscale saltbushOther:
other grasses = forbs = other shrubsAdditional:
Functional /structural groups may appropriately contain non-native species if their ecological function is the same as the native species in the reference state (e.g. crested wheatgrass and Russian wildrye may substitute for mid stature cool season perennial native bunchgrasses.). Biological soil crust is variable in its expression on this site and is measured as a component of ground cover. Forbs can be expected to vary widely in their expression in the plant community based upon departures from average growing conditions. -
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
During years with average to above average precipitation, there should be very little recent mortality or decadence apparent in either the shrubs or grasses. Some bunchgrass and shrub mortality may occur during severe droughts, particularly on the shallower and coarser soils associated with this site. -
Average percent litter cover (%) and depth ( in):
Litter cover includes litter under plants. Most litter will be fine litter. Depth should be 1-2 leaf thickness in the interspaces and up to 1/2” under canopies. Litter cover may increase to 15-25% following years with favorable growing conditions. Excess litter may accumulate in absence of disturbance. Vegetative production may be reduced if litter cover exceeds 40%. -
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
700-775#/acre. Even the most stable communities exhibit a range of production values. Production will vary between communities and across the MRLA. Refer to the community descriptions in the ESD. Production will differ across the MLRA due to the naturally occurring variability in weather, soils, and aspect. The biological processes on this site are complex; therefore, representative values are presented in a land management context. -
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:
Cheatgrass, halogeton, green rabbitbrush, annual forbs, broom snakeweed, Utah juniper, purple threeawn, medusahead rye. -
Perennial plant reproductive capability:
All perennial plants should have the ability to reproduce sexually or asexually, except in drought years. Density of plants indicates that plants reproduce at level sufficient to fill available resource. Within capability of site there are no restrictions on seed or vegetative reproductive capacity.
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