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.
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): 047X–Wasatch and Uinta Mountains
MLRA 47 occurs in Utah (86 percent), Wyoming (8 percent), Colorado (4 percent), and Idaho (2 percent). It encompasses approximately 23,825 square miles (61,740 square kilometers). The northern half of this area is in the Middle Rocky Mountains Province of the Rocky Mountain System. The southern half is in the High Plateaus of the Utah Section of the Colorado Plateaus Province of the Intermontane Plateaus. Parts of the western edge of this MLRA are in the Great Basin Section of the Basin and Range Province of the Intermontane Plateaus. The MLRA includes the Wasatch Mountains, which trend north and south, and the Uinta Mountains, which trend east and west. The steeply sloping, precipitous Wasatch Mountains have narrow crests and deep valleys. Active faulting and erosion are a dominant force in controlling the geomorphology of the area. The Uinta Mountains have a broad, gently arching, elongated shape. Structurally, they consist of a broadly folded anticline that has an erosion-resistant quartzite core. The Wasatch and Uinta Mountains have an elevation of 4,900 to about 13,500 feet (1,495 to 4,115 meters).
The mountains in this area are primarily fault blocks that have been tilted up. Alluvial fans at the base of the mountains are recharge zones for the basin fill aquifers. An ancient shoreline of historic Bonneville Lake is evident on the footslopes along the western edge of the area. Rocks exposed in the mountains are mostly Mesozoic and Paleozoic sediments, but Precambrian rocks are exposed in the Uinta Mountains. The Uinta Mountains are one of the few ranges in the United States that are oriented west to east. The southern Wasatch Mountains consist of Tertiary volcanic rocks occurring as extrusive lava and intrusive crystalline rocks.
The average precipitation is from 8 to 16 inches (203 to 406 mm) in the valleys and can range up to 73 inches (1854 mm) in the mountains. In the northern and western portions of the MLRA, peak precipitation occurs in the winter months. The southern and eastern portions have a greater incidence of high-intensity summer thunderstorms; hence, a significant amount of precipitation occurs during the summer months. The average annual temperature is 30 to 50 degrees Fahrenheit (-1 to 15 C). The freeze-free period averages 140 days and ranges from 60 to 220 days, generally decreasing in length with elevation.
The dominant soil orders in this MLRA are Aridisols, Entisols, Inceptisols, and Mollisols. The lower elevations are dominated by a frigid temperature regime, while the higher elevations experience cryic temperature regimes. Mesic temperature regimes come in on the lower elevations and south facing slopes in the southern portion of this MLRA. The soil moisture regime is typically xeric in the northern part of the MLRA, but grades to ustic in the extreme eastern and southern parts. The mineralogy is generally mixed and the soils are very shallow to very deep, generally well drained, and loamy or loamy-skeletal.
LRU notes
Major Land Resource Unit 47A is located in the northern half of the Middle Rocky Mountains Province of the Rocky Mountain System. This MLRA includes the Wasatch Mountains which tend to run north and south. These steeply sloping, precipitous mountains have narrow crests and deep valleys. They are primarily fault blocks that have been tilted up. The alluvial fans located at the base of these mountains are important recharge zones for valley aquifers.
The soils of this site are deep and well-drained with thick, dark brown surface layers. They formed in alluvium, colluvium and/or residuum derived from various sedimentary and metemorphic rocks. Surface textures are loams and are underlain by loam or clay layers. Rock fragments may occur on the soil surface and throughout the soil profile, but do not exceed 35 percent of the soil volume. Lime horizons may occur at depths greater than 36 inches, but the overlying soil is usually noncalcareous. Permeability is slow to moderate. Water holding capacity in the upper 40 inches of soil ranges from 4.1 to 7.7 inches of water. The soil moisture regime is xeric and the soil temperature regime is frigid.
This site occurs on mountain slopes, canyons, hills and alluvial fans at elevations between 5,400 and 8,000 feet. It is most commonly found on north and east facing slopes, but can occur on other aspects. Slopes range from 10 to 60 percent. Flooding and ponding do not occur on this site.
Table 2. Representative physiographic features
Landforms
(1) Mountain slope (2) Canyon (3) Hill
Flooding frequency
None
Ponding frequency
None
Elevation
5,400–8,000 ft
Slope
10–60%
Aspect
N, NE, E
Climatic features
The climate of this site is cool and quite humid with cold snowy winters and cool dry summers. The average annual precipitation varies from 19 to 25 inches with an average of around 22. Distribution is 55 to 60 percent during the plant dormant period (October to March). This is the most dependable supply for plant growth. Lower precipitation and high evapo-transpiration rates during July, August and September causes slowing down in growth of all plant species and dormancy in most of the grasses and forbs.
Table 3. Representative climatic features
Frost-free period (average)
98 days
Freeze-free period (average)
128 days
Precipitation total (average)
22 in
Bar
Line
Figure 2. Monthly precipitation range
Bar
Line
Figure 3. Monthly average minimum and maximum temperature
Figure 4. Annual precipitation pattern
Figure 5. Annual average temperature pattern
Influencing water features
Due to its landscape position, this site is not typically influenced by streams and wetlands.
Wetland description
N/A
Soil features
The soils of this site are deep and well-drained with thick, dark brown surface layers. They formed in alluvium, colluvium and residuum derived from various sedimentary and metamorphic rocks. Surface textures are loams and are underlain by loam or clay layers. Rock fragments may occur on the soil surface and throughout the soil profile, but do not exceed 35 percent of the soil volume. Lime horizons may occur at depths greater than 36 inches, but the overlying soil is usually non-calcareous. Permeability is slow to moderate. Water holding capacity in the upper 40 inches of soil ranges from 4.1 to 6.1 inches of water. The soil moisture regime is xeric and the soil temperature regime is frigid.
Table 4. Representative soil features
Parent material
(1) Igneous, metamorphic and sedimentary rock
Surface texture
(1) Gravelly loam
(2) Silt loam
(3) Gravelly clay loam
Family particle size
(1) Loamy
Drainage class
Well drained
Permeability class
Moderately slow to moderate
Soil depth
40–60 in
Surface fragment cover <=3"
13%
Surface fragment cover >3"
3%
Available water capacity (0-40in)
4.1–6.1 in
Calcium carbonate equivalent (0-40in)
25%
Electrical conductivity (0-40in)
2 mmhos/cm
Sodium adsorption ratio (0-40in)
2
Soil reaction (1:1 water) (0-40in)
6.1–7.8
Subsurface fragment volume <=3" (Depth not specified)
30%
Subsurface fragment volume >3" (Depth not specified)
8%
Ecological dynamics
It is impossible to determine in any quantitative detail the Historic Climax Plant Community (HCPC) for this ecological site because of the lack of direct historical documentation preceding all human influence. In some areas, the earliest reports of dominant plants include the cadastral survey conducted by the General Land Office, which began in the late 19th century for this area (Galatowitsch 1990). However, up to the 1870s the Shoshone Indians, prevalent in northern Utah and neighboring states, grazed horses and set fires to alter the vegetation for their needs (Parson 1996). In the 1860s, Europeans brought cattle and horses to the area, grazing large numbers of them on unfenced parcels year-long (Parson 1996). Itinerant and local sheep flocks followed, largely replacing cattle as the browse component increased.
Below is a State and Transition Model diagram to illustrate the “phases” (common plant communities), and “states” (aggregations of those plant communities) that can occur on the site. Differences between phases and states depend primarily upon observations of a range of disturbance histories in areas where this ESD is represented. These situations include grazing gradients to water sources, fence-line contrasts, patches with differing dates of fire, herbicide treatment, tillage, etc. Reference State 1 illustrates the common plant communities that probably existed just prior to European settlement.
The major successional pathways within states, (“community pathways”) are indicated by arrows between phases. “Transitions” are indicated by arrows between states. The drivers of these changes are indicated in codes decipherable by referring to the legend at the bottom of the page and by reading the detailed narratives that follow the diagram. The transition between Reference State 1 and State 2 is considered irreversible because of the naturalization of exotic species of both flora and fauna, possible extinction of native species, and climate change. There may have also been accelerated soil erosion.
When available, monitoring data (of various types) were employed to validate more subjective inferences made in this diagram. See the complete files in the office of the State Range Conservationist for more detail.
Plant Community Narratives:
The plant communities shown in this State and Transition Model may not represent every possibility, but are probably the most prevalent and recurring plant communities. As more monitoring data are collected, some phases or states may be revised, removed, and/or new ones may be added. None of these plant communities should necessarily be thought of as “Desired Plant Communities.” According to the USDA NRCS National Range & Pasture Handbook (USDA-NRCS 2003), Desired Plant Communities (DPC’s) will be determined by the decision-makers and will meet minimum quality criteria established by the NRCS. The main purpose for including descriptions of a plant community is to capture the current knowledge at the time of this revision.
As range condition deteriorates due to overgrazing, slender wheatgrass and bluebunch wheatgrass decrease while mountain big sagebrush increases. Burning the vegetation causes mountain big sagebrush to decrease in density and grass, rabbitbrush, snowberry and serviceberry to increase. Plant species not a part of the climax plant community that are most likely to invade the site if plant cover deteriorates are: cheatgrass, annual forbs, milkweed, stickseed, tarweed, and snakeweed.
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
over an extended period of time and in combination with prescribed grazing
State 1 Reference State
The Reference State is a description of this ecological site just prior to Euro-American settlement but long after the arrival of Native Americans. The description of the Reference State was determined by NRCS Soil Survey Type Site Location information and familiarity with rangeland relict areas where they exist. The least modified plant community (1.1) within the Reference State would have been a sagebrush-dominated stand with mountain big sagebrush (Artemisia tridentate spp. vaseyana), mountain snowberry (Symphoricarpos oreophilus) and associated bunch grasses such as bluebunch wheatgrass (Pseudoroegeneria spicata), Nevada bluegrass (Poa secunda) and slender wheatgrass (Elymus trachycaulus). Forbs such as arrowleaf balsamroot (Balsamorhiza sagittata), sticky purple geranium (Geranium viscosissimum) and fleabane (Erigeron sp.) would be present. Fire is believed to be the dominant disturbance force in natural big sagebrush communities. The reference plant community (1.1) would have been relatively stable with occasional use by wildlife. Following a natural fire (1.1a) and depending on the severity, would have killed most if not all of the sagebrush favoring the sprouting shrubs and bunchgrasses (1.2). Over time and without any further disturbances (1.2a) sagebrush and other non-sprouting shrubs would slowly come back into the site (1.3), however the sprouting shrubs and bunch grasses would still dominate the site. If there were another fire to occur on the site (1.3a) the site would return to community phase 1.2. If community phase 1.3 continued to experience no disturbances over a longer period of time (1.3b) it would eventually show a co-dominance between mountain big sagebrush and the other shrubs on the site. A more complete list of species by lifeform for the Reference State is available in the accompanying tables in the “Plant Community Composition by Weight and Percentage” section of this document.
Community 1.1 Mountain big sagebrush/other shrubs/ perennial grasses
Figure 6. CP1.1
The least modified plant community within the Reference State would have been a mountain big sagebrush-dominated with associated deciduous shrubs such as mountain snowberry, antelope bitterbrush, serviceberry and associated perennial grasses such as bluebunch wheatgrass and slender wheatgrass. Arrowleaf balsamroot, sticky purple geranium and erigeron sp. would have been the commonly associated forbs. Percent composition would have been 45 percent shrubs, 45 percent grasses and 15 percent forbs.
Figure 7. 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
698
923
1148
Shrub/Vine
698
923
1148
Forb
155
205
255
Total
1551
2051
2551
Table 6. Ground cover
Tree foliar cover
0%
Shrub/vine/liana foliar cover
24-26%
Grass/grasslike foliar cover
34-36%
Forb foliar cover
9-11%
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/ Grasslike
Forb
<0.5
–
–
–
–
>0.5 <= 1
–
–
–
9-11%
>1 <= 2
–
–
34-36%
–
>2 <= 4.5
–
24-26%
–
–
>4.5 <= 13
–
–
–
–
>13 <= 40
–
–
–
–
>40 <= 80
–
–
–
–
>80 <= 120
–
–
–
–
>120
–
–
–
–
Community 1.2 Sprouting shrubs with perennial bunch grasses.
Fire is a naturally occurring disturbance on this site and would have kept shrubs like mountain big sagebrush and antelope bitterbrush less dominant. Sprouting shrubs like mountain snowberry and serviceberry and perennial grasses would have become the dominant aspect of this site.
Community 1.3 Non-sprouting shrubs start becoming re-established
Non-sprouting shrubs start becoming re-established from seed over time. Sprouting shrubs and perennial grasses are still the dominant aspect of this site.
Pathway 1.1a Community 1.1 to 1.2
A naturally occurring fire would have killed all the non-sprouting shrubs like mountain big sagebrush. As the site recovered, it would be converted to the sprouting shrubs with perennial bunchgrasses community.
Pathway 1.2a Community 1.2 to 1.3
Over time and without the occurrence of a natural disturbance, such as fire, non-sprouting shrubs like mountain big sagebrush, antelope bitterbrush and alderleaf mountain mahogany would become re-established on the site.
Pathway 1.3b Community 1.3 to 1.1
Over time and with the absence of a natural disturbance, like fire, the non-sprouting shrubs will continue becoming more abundant to a point where they are co-dominant with the sprouting shrubs.
Pathway 1.3a Community 1.3 to 1.2
In the event that there is another natural disturbance, like a fire, the site would return to the sprouting shrubs with perennial bunch grasses community.
State 2 Current Potential
State 2 is identical to State 1 in form and function, with the exception of the presence of non-native plants and animals, possible extinctions of native species, and a different climate. State 2 is a description of the ecological site shortly following Euro-American settlement, which can be regarded as the current potential. The least modified plant community (2.1) within State 2 is a sagebrush (Artemisia tridentate spp. vaseyana) dominated state with mountain snowberry (Symphoricarpos oreophilus) and associated bunch grasses such as bluebunch wheatgrass (Pseudoroegeneria spicata), Nevada bluegrass (Poa secunda) and slender wheatgrass (Elymus trachycaulus). Forbs such as arrowleaf balsamroot (Balsamorhiza sagittata), sticky purple geranium (Geranium viscosissimum) and fleabane (Erigeron sp.) would be present. A common non-native species in this state is cheatgrass. Fire is believed to be the dominant disturbance force in natural big sagebrush communities. Following brush management or fire (2.1a) and depending on the severity, would have killed most if not all of the sagebrush, and other non-sprouting shrubs, favoring the sprouting shrubs and bunchgrasses (2.2). This plant community is relatively stable under mixed use by wildlife and livestock. However, heavy utilization by bison, elk, horses, and domestic cattle on these sites during the growing season (2.1b) would deplete the grasses and deciduous shrubs creating site that is dominated by mountain big sagebrush (2.3). In community 2.2, when management, such as prescribed grazing, can be combined with time (2.2a) to allow the site to recover returning to community 2.1. However if the community continues to be over utilized by both wildlife and domestic livestock, and possibly in combination with a natural or man caused disturbance (2.2b) this community (2.2) can be degraded to community 2.4 which is dominated by rhizomatous grasses with unpalatable sprouting shrubs and forbs. In community 2.3 when management, such as prescribed grazing coupled with time, (2.3a) the sprouting shrubs and perennial grasses can have an opportunity to recover and recolonize the site and return to community 2.1. In community 2.3, when it experiences a disturbance such as brush management or fire, coupled with management like prescribed grazing (2.3b) it can drive the site to a more stable and diverse community 2.2. However, when community 2.3 continues to be over utilized and this is coupled with a disturbance such as brush management or fire (2.3c) it can drive the site to an undesirable community 2.4.
Community 2.1 Mountain big sagebrush with perennial grasses and deciduous
The least modified community within the mountain big sagebrush/deciduous shrub/introduced state. This is a mountain big sagebrush dominated community with an abundance of deciduous shrubs such as mountain snowberry, antelope bitterbrush and serviceberry. Community is also characterized by an abundance of native perennial grasses such as, bluebunch wheatgrass, slender wheatgrass and Nevada bluegrass. Associated forbs on this site may consist of arrowleaf balsamroot, sticky purple geranium and erigeron sp. Introduced species likely to occur on this site are cheatgrass, annual forbs, milkweed and stickseed.
Community 2.2 Sprouting shrubs with perennial grasses with introduced annuals present
This community represents what the site would look like following brush management or a natural or prescribed fire. Depending on the severity of the fire/management practice, some or all of the non-sprouting shrubs would be killed. This would open up resources for the sprouting shrubs and native perennial grasses subsequently they would be the dominant aspect of the site.
Community 2.3 Depauperate sagebrush with conifers possibly present
This community represents what the site would look like following a long period of over grazing and browsing. The more palatable species would be heavily utilized giving a competitive advantage to species such as mountain big sagebrush. Over time sagebrush would be the dominant aspect of the site with a low diversity of the other native species that normally occur on the site.
Community 2.4 Rhizomatous grasses with unpalatable sprouting shrubs and forbs with low growing grasses
This community represents the site when there has been continued overgrazing/browsing for an extended period of time, followed by a disturbance such as a brush management treatment or natural/prescribed fire. Species diversity was already low (2.3). The overutilization of the desirable native vegetation coupled with the fire has reduced the site to unpalatable sprouting shrubs and forbs along with low growing grasses.
Pathway 2.1a Community 2.1 to 2.2
A naturally occurring fire would have killed all the non-sprouting shrubs like mountain big sagebrush. As the site recovered, it would be converted to the sprouting shrubs with perennial bunchgrasses community.
Pathway 2.1a Community 2.2 to 2.1
Over time and without the occurrence of a natural disturbance, such as fire, non-sprouting shrubs like mountain big sagebrush, antelope bitterbrush and alderleaf mountain mahogany would become re-established on the site.
Pathway 2.3b Community 2.3 to 2.1
Over time and with the absence of a natural disturbance, like fire, the non-sprouting shrubs will continue becoming more abundant to a point where they are co-dominant with the sprouting shrubs.
Pathway 2.3a Community 2.3 to 2.2
In the event that there is another natural disturbance, like a fire, the site would return to the sprouting shrubs with perennial bunch grasses community.
Pathway 2.4a Community 2.4 to 2.2
This pathway represents that over time, along with prescribed grazing that the sprouting shrubs and native perennial grasses would eventually re-establish and return the site back to community 2.2.
State 3 Seeded State
This State occurs where historic excessive livestock grazing reduced canopy cover, and in an attempt to prevent any additional excessive erosion it was intentionally seeded with species such as smooth brome and/or crested wheatgrass. Do to the decreased canopy cover and increased erosion, and rangeland seeding is utilized, either rangeland drilled or aerial application with predominately introduced species.
Community 3.1 Range seeding with perennial introduced species
Figure 8. CP3.1
Figure 9. CP3.1_2
This community represents a time shortly following a brush management treatment/fire in addition to the range seeding. Non-sprouting shrubs have been greatly reduced and sprouting shrubs have not had adequate time to become re-established. Introduced and native grass species with a few sprouting shrubs dominate the site.
Community 3.2 Sprouting shrubs becoming co-dominant with perennial grasses
This community phase represents the site over a 5 to 10 year period of time under normal climatic conditions. The desirable sprouting shrubs have had adequate time to re-establish and become co-dominant with the perennial grasses. Non-sprouting shrubs have also started to re-establish on the site as well. It is imperative that prescribed grazing must be implemented in order for this community to be persist.
Pathway 3.1a Community 3.1 to 3.2
Over an extended period of time and in combination with prescribed grazing, the native desirable sprouting shrubs begin to become well established.
Transition T1a State 1 to 2
The simultaneous introduction of exotic species, both plants and animals, and possible extinctions of native flora and fauna, along with climate change, will cause State 1 to transition to State 2. A return pathway back to State 1 would be impracticable because of these issues.
Transition T2a State 2 to 3
When land managers or landowners have made the decision that the herbaceous understory species are so depleted and undesirable, and the biological, hydrological and soil resources are at risk, introduced and native perennial grasses are utilized in a range seeding. This often occurs in combination with a natural/prescribed fire or other brush management treatment.
Additional community tables
Table 8. Community 1.1 plant community composition
This site provides habitat for a variety of wildlife. Invertebrate species found on this site include native mountain snails (Oreohelix spp.), especially in association with limestone outcrops. Great Basin spadefoot toad is the only amphibian likely to occur. Common reptile species include skinks, greater short-horned lizard, Great Basin rattlesnake, smooth green snake, and Sonoran mountain kingsnake. This site is important habitat for Columbia sharp-tailed grouse, dusky grouse, and ruffed grouse. Many songbirds occur on this site, including flycatchers, wrens, warblers, towhees, and sparrows. Several woodpeckers and sharp-shinned hawks are also present. Berry-producing shrubs are important food sources for grouse and songbirds, particularly in fall and winter. Mammals on this site include shrews, numerous species of bats, mountain cottontail, squirrels and other rodents, gray and red foxes, black bear, long-tailed weasel, skunks, bobcat, mountain lion, moose, mule deer, and elk. This site provides excellent forage and cover for deer and elk and is often located in critical winter habitat.
This site supports a good volume and a wide variety of species of grasses, forbs and shrubs. It provides nutritious forage for sheep, cattle, horses and goats. It can be grazed in spring, summer, and fall.
Hydrological functions
This site occurs on gentle to steep mountainsides and ridges. The soils of this site are deep, well-drained, and have thick dark colored surface layers. They are underlain by medium to fine textured layers that may contain gravel and cobble. Some soils may have lime horizons below 36 inches, but the overlying soil is usually non-calcareous. These soils occur on all exposures, but predominantly north and east. Intake rate is moderate and water movement through the soil is moderate to slow. Roots penetrate the soil readily. These soils have a high water holding capacity, ranging from about 10 to 14 inches. Rock fragments are variable throughout the profile, but are less than 35 percent by volume. Stone or cobble may occur as a surface mantle. Under proper management, these soils have little surface runoff and slight or no erosion.
Recreational uses
This site has good values for aesthetics and natural beauty. It has a large number of forbs and shrubs which have flowers in bloom from early spring throughout the summer and into the fall. It has a combination of grasses, forbs, small shrubs and large shrubs which offer some possibilities for screening and value as camping and picnicking areas. Hunting for upland game birds, snowshoe hare, elk and mule deer is good to excellent on this site. Fishing is opportune in streams through and adjacent to this site. This site has values for snowmobiling during a fairly long period of the winter season.
Wood products
No values exist for lumber. Some values exist for fuel for campfires.
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.
Other references
Galatowitsch, S. M. 1990. Using the original land survey notes to reconstruct pre-settlement landscapes in the American West. Great Basin Naturalist 50:181-191. Keywords: [Western U.S., conservation, history, human impact]
Parson, R. E. 1996. A History of Rich County. Utah State Historical Society, County Commission, Rich County, Utah. Keywords: [Rich County, Utah, Historic land use, European settlements]
USDA-NRCS. 2003. National Range and Pasture Handbook. in USDA, editor, USDA-Natural Resources Conservation Service-Grazing Lands Technology Institute. Keywords: [Western US, Federal guidelines, Range pasture management]
West, N. E. 2000. Synecology and disturbance regimes of sagebrush steppe ecosystems. Pages 15-26 in Entwistle, P.G., A.M. DeBolt, J.H. Kaltenecker and K. Steenhof (compilers) Sagebrush Steppe Ecosystems Symposium Proceedings. Bureau of Land Management, Boise State University, Boise, Idaho, Publication No. BLM/ID/PT-0011001+1150. Keywords: [Intermountain West, Sagebrush Steppe, plant ecology, management]
Darryl Trickler, Tim Watson Karen Fullen M. Dean Stacy
Approval
Kendra Moseley, 2/05/2025
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)
V. Keith Wadman (NRCS Retired).
Contact for lead author
shane.green@ut.usda.gov
Date
10/24/2012
Approved by
Kendra Moseley
Approval date
Composition (Indicators 10 and 12) based on
Annual Production
Indicators
Number and extent of rills:
None to Rare. Some minor rill development may occur on steeper slopes (> 20%) or on areas located below exposed bedrock or other water shedding areas where increased runoff may occur. Where these rills are present, they should be fairly short (3-6 feet), < 1 inch deep and somewhat widely spaced (4-8 feet). Minor rill development may be observed on all slopes following major thunderstorm or spring runoff events but should heal during the next growing season.
Presence of water flow patterns:
Rare. Some very minor evidence of water flow patterns may be found winding around perennial plant bases. They show little evidence of current erosion. They are expected to be short (3-6 feet), stable, sinuous and normally not connected. There may be very minor evidence of deposition. Evidence of water flow may increase somewhat in slopes > 20%.
Number and height of erosional pedestals or terracettes:
Perennial vegetation shows very little evidence of erosional pedestalling (< 1% of individual plants). Plant roots are covered and most litter remains in place around plant crowns. Terracettes should be absent or, if present, stable. A slight increase in both pedestal and terracette development may occur with increasing slope.
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are
not bare ground):
Bare ground ranges from 15% - 20%. Soil surface may be covered by 20 to 35% coarse fragments. Bare ground openings should not be greater than 1 foot in diameter and should normally not be connected.
Number of gullies and erosion associated with gullies:
None to Rare at site level. Scattered landscape level gully channels, however, are a normal component of basin/range environments. Where landscape gullies are present, they should be stable, partially vegetated on their sides and bottoms, with no evidence of head-cutting. Some slight increase in disturbance may be evident following significant weather events or when gullies convey considerable runoff from higher elevation rocky or naturally eroding areas.
Extent of wind scoured, blowouts and/or depositional areas:
None. No evidence of wind generated soil movement is present. Wind caused blowouts and deposition are not present.
Amount of litter movement (describe size and distance expected to travel):
Most litter resides in place with some redistribution caused by water movement. Minor litter removal may occur in flow channels with deposition occurring within 1 to 2 feet at points of obstruction. The majority of litter accumulates at the base of plants. Some grass leaves and small twigs (grass stems) may accumulate in soil depressions adjacent to plants. Woody stems are not likely to move. However, some litter movement is expected (up to 6 feet) with increases in slopes >20% and/or increased runoff resulting from heavy thunderstorms.
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range
of values):
This site should have a soil stability rating of 5 or 6. Soil surface textures are typically loams, very fine sandy loams and silt loams.
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
(Barfuss) Soil surface 0-10 inches. Surface texture is a silt loam which may have an organic mat of partially decomposed leaves and twigs 1 inch deep on the surface; color is dark gray (10YR 4/1); and structure is moderate medium subangular blocky. Mollic epipedon ranges to 27 inches. Use the specific information for the soil you are assessing found in the published soil survey to supplement this description.
Effect of community phase composition (relative proportion of different functional groups) and spatial
distribution on infiltration and runoff:
Perennial vegetation produces sufficient cover and spatial arrangement to intercept most raindrops and reduce raindrop splash erosion. Litter on soil surface and cryptogamic crusting, where present, also protects soil from splash erosion and encourages a higher rate of infiltration. Plant spatial distribution should slow runoff, allowing additional time for infiltration. Bare spaces are expected to be small and irregular in shape and are usually not connected. Vegetative structure is usually adequate to capture snow and ensure that snowmelt occurs in a controlled manner, allowing maximum time for infiltration, and reducing runoff and erosion in all but the most extreme storm events. When perennial grasses and shrubs decrease due to natural events including drought, insect damage, etc., which reduce ground cover and increase bare ground, runoff is expected to increase and associated infiltration reduced.
Presence and thickness of compaction layer (usually none; describe soil profile features which may be
mistaken for compaction on this site):
None. Some soils may have argillic horizons or other natural textural variability within their profiles, these should not be mistaken for a compaction pan.
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):
A wide variety of other perennial grasses and both perennial and annual forbs can be expected to occur in the plant community.
Additional:
Natural disturbance regimes include fire, drought, and insects. Assumed fire cycle of 40 to 60+ years. Functional/structural groups may appropriately contain non-native species if their ecological function is the same as the native species in the reference. Following a disturbance such as fire, drought, rodents or insects that remove woody vegetation, forbs and perennial grasses (herbaceous species) may dominate the community for a period of time. If a disturbance has not occurred for an extended period of time, woody species may continue to increase. These conditions would reflect different functional community phases within the reference state.
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or
decadence):
Slight decadence in the principle shrubs could occur near the end of the fire cycle or during periods of extended drought, or insect infestations. In general, a mix of age classes should be expected with some dead and decadent plants present.
Average percent litter cover (%) and depth ( in):
Litter cover will be heavier under plants. Most litter will be herbaceous and depths of 1 to 2 inches would be considered normal. Perennial vegetation should be well distributed on the site.
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
Annual production in air-dry herbage should be approximately 2000 - 2100 #/acre on an average year but could range from 1600 - 2500 #/acre during periods of prolonged drought or above average precipitation.
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, Allysum, mustard species, Canada thistle, black medic, Utah juniper, Gambel oak (in exaggerated amounts).
Perennial plant reproductive capability:
All perennial plants should have the ability to reproduce in all years, except in extreme drought years. Green rabbitbrush sprouts vigorously following fire. There are no restrictions on either seed or vegetative reproduction. Some seedling recruitment of major species is present during average and above average growing years.
The Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.
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