Physiographic features

The Loamy Wyoming Front (Ly) ecological site (R046XH122WY) is located within LRU “H” in MLRA “46.” This ecological site occurs in foothill landscapes on hillslopes, landslides, ridges and eroded fan remnant landforms (see definitions below). The slope ranges from level to 15%. This site occurs on all aspects.
eroded fan remnant –All, or a portion of an alluvial fan that is much more extensively eroded and dissected than a fan remnant; sometimes called an erosional fan remnant (FFP). It consists primarily of a) eroded and highly dissected sides (eroded fan-remnant sideslopes) dominated by hillslope positions (shoulder, backslope, etc.), and b) to a lesser extent an intact, relatively planar, relict alluvial fan “summit” area best described as a tread.
hillslope –A generic term for the steeper part of a hill between its summit and the drainage line, valley flat, or depression floor at the base of the hill. Compare – mountain slope

Table 2. Representative physiographic features

Climatic features

Annual precipitation ranges from 15-19 inches per year. Wide fluctuations may occur in yearly precipitation and result in more dry years than those with more than normal precipitation. Temperatures show a wide range between summer and winter and between daily maximums and minimums. This is predominantly due to the high elevation and dry air, which permits rapid incoming and outgoing radiation. Cold air outbreaks in winter move rapidly from northwest to southeast and account for extreme minimum temperatures. Extreme storms may occur during the winter, but most severely affect ranch operations during late winter and spring. Prevailing winds are from the southwest, and strong winds are less frequent than over other areas of Wyoming. Occasional storms, however, can bring brief periods of high winds with gusts exceeding 50 mph. Growth of native cool season plants begins about May 15 and continues to about August 15.

The following information is from the “Merna” climate station:

Minimum Maximum 5 yrs. out of 10 between

Frost-free period (days): 11 59 July 5 – August 15
Freeze-free period (days): 43 94 June 15 – August 24

Annual Precipitation (inches): <9.15 >20.17 (2 years in 10)

Average annual precipitation: 15.21 inches

Average annual air temperature: 34.2F (20.3F Avg. Min. to 48.2F Avg. Max.)

Table 3. Representative climatic features

Influencing water features

None

Soil features

The soils of this site are deep to moderately deep (greater than 20" to bedrock), and well-drained. Textures range from loams to very fine sandy loam on the coarse end to light clay loam (<30% clay content) on the heavy end. The most common textures include loam, silt loam, and sandy clay loam. A highly common scenario is to have a 1 to 3” cap of sandy loam over a sandy clay loam due to young soil development of weathered sandstone and shale parent materials.

Major Soil Series correlated to this site includes: Millerlake, Beaveridge, and Beavmid series.

Typical taxonomy: fine-loamy, mixed, superactive, Ustic Argicryolls


Other Soil Series correlated to this site in MLRA 34A include: Onionspring, Leavitt, and Philipsburg series.

Table 4. Representative soil features

Animal community

Animal Community
The following table lists suggested initial stocking rates for cattle under continuous season-long grazing under normal growing conditions. These are conservative estimates that should be used only as guidelines in the initial stages of the conservation planning process. Often, the current plant composition does not entirely match any particular plant community (as described in this ecological site description). Because of this, a field visit is recommended, in all cases, to document plant composition and production. More precise carrying capacity estimates should be calculated using field information along with animal preference data, particularly when grazers other than cattle are involved. Under more intensive grazing management, improved harvest efficiencies can result in an increased carrying capacity, but recovery time for upland sites is much longer than in a low intensity system.
If distribution problems occur, stocking rates must be reduced or facilitating conservation practices (i.e. cross-fencing, water development) used to maintain plant health and vigor.

Plant Community Production Carrying Capacity*
(lb./ac) Low-RV-High AUM/AC AC/AUM
Sagebrush/Bunchgrass 1200-1800-2200 0.25 4
Bunchgrass/Sagebrush 1200-1800-2200 0.32 3
Sagebrush/Mat forb/bluegrass 800-1200-1400 0.1 10
Mat forb/bluegrass 600-900-1200 0.15 7
Dense Sagebrush 1000-1400-2000 0.13 8
Non-natives/Sagebrush 800-1400-2000 0.28 4



* - Continuous, season-long grazing by cattle under average growing conditions.
**Calculation for these stocking rates are as follows: using RV values for production, take only forage palatable to cattle and multiply by 0.25 harvest efficiency and divide by 913 (pounds of air dried weight forage per Animal Unit Month based on intake rate of 2.6%) to arrive at carrying capacity

Grazing by domestic livestock is one of the major income-producing industries in the area. Rangeland in this area may provide yearlong forage for cattle, sheep, or horses. During the dormant period, protein supplement is recommended because the quality does not meet minimum livestock requirements.
Distance to water, shrub density, and slope can affect grazing capacity within a management unit. Adjustments should be made for the area that is considered necessary for reduction of animal numbers. For example, 30% of a management unit may have 25% slopes and distances of greater than 1 mile from water; therefore the adjustment is only calculated for 30% of the unit (i.e. 50% reduction on 30% of the management unit). Fencing, slope length, management, access, terrain, kind and class of livestock, and breeds are all factors that can increase or decrease the percent of graze-able acres within a management unit. Adjustments should be made that incorporate these factors when calculating stocking rates

Wildlife

Reference State:
1.1 Big Sagebrush/Bunchgrass: This community phase provides optimal transitional and summer habitat for sage-grouse, mule deer, pronghorn, and elk. A diverse suite of herbaceous species also provide important micro-nutrient requirements for big game species throughout the year. These areas also provide high quality bird nesting habitat where sagebrush canopy and residual bunchgrasses hide nests and young from predators. This very common community is used widely as migration and stopover habitat by big game. Spring green-up of grass is a critical nutritional component of this community for migrating big game.

1.2 Bunchgrass/WY Big Sagebrush: This community phase tends to have higher herbaceous plant diversity that may attract more diverse wildlife use. The plant community provides suitable forage and cover for sagebrush obligate species. The more open canopy promotes higher diversity and quantity of forbs that are important for early sage-grouse brood­rearing habitat. It also provides high quality habitat for mule deer, elk and pronghorn as they transition between winter and summer ranges. This very common community is used widely as migration and stopover habitat by big game. Spring green-up of grass and forb diversity is a critical nutritional component of this community for migrating big game. This community also provides suitable habitat for burrowing animals.

Grazing Resistant State:
2.1 Big Sagebrush/Mat Forb/Bluegrass: This community phase is variable in its value to wildlife. The value of the sagebrush community is similar to the reference state but the value of the grass community decreases. In periods of high plant vigor, the herbaceous understory provides cover for nesting birds and small mammals. In periods of drought and low plant vigor, the herbaceous understory is short and not dense enough to provide adequate cover and habitat value declines. Diversity is low, and mat-forming forbs often occupy the space and nutrients needed for more desirable forbs.

2.2 Mat Forb/Bluegrass: This community phase is variable in its value to wildlife. Value is low for species dependent on sagebrush unless in close proximity to areas with sagebrush cover. In periods of high plant vigor, herbaceous species provide cover for some birds and small mammals. In periods of drought and low plant vigor, the herbaceous community is often too short and not dense enough to provide adequate cover and habitat. Plant and animal diversity is low.

Dense Sagebrush State:
3.1 Dense Sagebrush: This community phase provides potential foraging habitat for big game and sage­grouse when the sagebrush plants are in a healthy condition. If the sagebrush is old and has poor leader production, it may not be providing forage for browsing animals either. The lack of herbaceous species limits the value of the site for birds and small mammals due to the lack of cover in the interspaces of the sagebrush plants. The lack of plant diversity limits the diversity of insects used by wildlife species.

Invaded State:
4.1 Non-natives: This community phase is highly variable in its value to wildlife. It typically is less diverse, has lower forage value and has limited structure that wildlife need for cover. This state is vulnerable to repeated disturbance which can result in a complete loss of value for wildlife. In addition, sites in this state are more susceptible to invasion of non-native species, further degrading the value for wildlife.

Highly Disturbed State:
5.2 Reclaimed: This community phase is highly variable in its value to wildlife. Reclamation success, size and configuration of the reclaimed area, the species planted, and the time it takes for plants to establish will determine the value of the site for wildlife. A fully reclaimed site containing a diversity of herbaceous and woody native plants can eventually provide the same wildlife habitat benefits as the reference state. In most cases, grasses and forbs establish early in the reclamation process, whereas shrubs take significantly longer to establish. Wildlife species dependent on herbaceous plant communities for forage (such as elk) will benefit from reclamation sooner than those species dependent on a mixed shrub/grass community. Suitable habitat for wildlife species that require tall, dense sagebrush (sage-grouse, pronghorn, mule deer, and sagebrush obligate songbirds) is likely possible within a decade, providing appropriate shrub species were planted. It is possible to achieve successful, diverse reclamation on linear disturbances (i.e. pipelines) without seeding shrubs, but it will take longer than a decade for seed from shrubs adjacent to the area to established on-site.

Hydrological functions

Water is the principal factor limiting forage production on this site. This site is dominated by soils in hydrologic group B (infiltration rate of 0.15-0.3 in/hr), with localized areas in hydrologic groups A (infiltration rate of 0.3 in/hr) and C (infiltration rate of 0.05-0.15 in/hr). Permeability ranges from rapid to moderate. Runoff potential for this site varies from low to moderate depending on soil hydrologic group and ground cover. In many cases, areas with greater than 75% ground cover have the greatest potential for high infiltration and lower runoff. Areas where ground cover is less than 50% have the greatest potential to have reduced infiltration and higher runoff (refer to Part 630, NRCS National Engineering Handbook for detailed hydrology information). Rills and gullies should not typically be present. Water flow patterns should be barely distinguishable if at all present. Litter typically falls in place, and signs of movement are not common unless slopes >10%. Chemical and physical crusts are rare to non-existent.

Recreational uses

This site provides some limited recreational opportunities for hiking, horseback riding, bird watching, and upland game hunting. The forbs have a variety of colors and shapes that appeal to photographers. This site provides valuable open space when located in large, un-fragmented landscapes.

Wood products

None

Other products

None

Other information

Similarity Index is based on species composition by air-dry weight. Calculations of allowable pounds per acre for each species are based on the sum of the maximum end of the production range or actual production (whichever is less) in the plant table for the Desired Plant Community until the maximum allowable is reached for the plant grouping. The sum is then divided by the Representative Value (RV) of total annual production for the Desired Plant Community.

Plant Preference Table:
https://docs.google.com/viewera=v&pid=sites&srcid=ZGVmYXVsdGRvbWFpbnxtbHJhMzRhfGd4OjIyZWEyYzIyMGE5NWE4MzM

Inventory data references

Inventory Data References (narrative):
Information presented was derived from 1988 Range Site Descriptions (Loamy Foothills and Mountains West – Ly 15-19W), NRCS clipping data, literature, field observations (based on sampled sites and observations), and personal contacts with range-trained personnel (i.e. agency specialists, landowners, land managers, and scientists).

Inventory Data References:
Data Source # of Records Sample Period State County
Field Data 12 (1.1 Reference) 1968-2018 WY Sublette
Field Data 11 (1.2 Reference) 1968-2018 WY Sublette
Field Data 13 (2.1 P.C.) 1978-2018 WY Sublette
Field Data 8 (2.2 P.C.) 1978-2018 WY Sublette
Field Data. 11 (3.1 P.C.) 1978-2018 WY Sublette
Field Obs. 2 (4.1 P.C.) 2004-2018 WY Sublette
Field Obs. 2 (4.2 P.C.) 2004-2018 WY Sublette

Other references

Bestelmeyer, B., & Brown, J. (2005). State-and-transition models 101: a fresh look at vegetation change. The Ouivira Coalition Newsletter, Vol. 7, No. 3.
Bestelmeyer, B., Brown, J., Havstad, K., Alexander, B., Chavez, G., & Herrick, J. (2003). Development and use of state and transition models for rangeland. Journal of Range Management, 56(2): 114-126.
Bestelmeyer, B., Herrick, J., Brown, J., Trujillo, D., & Havstad, K. (2004). Land management in the American Southwest: a state-and-transition approach to ecosystem complexity. Environmental Management, 34(1): 38-51.
Bukowski, B. E., & Baker, W. L. (2013). Hisotrical Fire Regimes, Reconstructed from Land-Survey Data, Led to Complexity and Fluctuation in Sagebrush Landscapes. Ecological Applications 23(3), 546-564.
Cagney, J., Bainter,, E., Budd, B., Christiansen, T., Herren, V., Holloran, M., . . . Williams, J. (2010, March). Grazing Influence, Objective Development, and Mangement in Wyoming's Greater Sage-Grouse Habitat. B-1203, 36. University of Wyoming.
Carney, J., Bainter, E., Budd, B., Christiansen, T., Herren, V., Holloran, M., . . . Williams, J. (2010). Grazing Influence, Objective Development, and Mangement in Wyoming's Greater Sage-Grouse Habitat. Unpublished, 36.
Chambers, J. C., Beck, J., Cambell, S., Carlson, J., Christiansen, T., Clause, K., . . . Pyke. (2016). Using Resilience and Resistance Concepts to Manage Threats to Sagebrush Ecosystems, Gunnison Sage-Grouse, and Greater Sage-Grouse in Their Eastern Range: A Strategic Multi-Scale Approach. Fort Collins, CO: USDA, Forest Service, Rocky Mountain Research Station: Gen. Tech. Rep. RMRS-GTR-356.
Clause, K., & Randall, J. (2014). Sage Die-Off Report. Pinedale, WY: unpublished.
Davies, K., Bates, J., & Nafus, A. (2012). Vegetation Response to Mowing Dense Mountain Big Sagebrush Stands. Rangeland Ecology and Management, 65: 268-276.
Derner, J. D., Schuman, G. E., Follett, R. F., & Vance, G. F. (2014). Plant and Soil Consequences of Shrub Management in a Big Sagebrush-Dominated Rangeland Ecosystem. Environment and Natural Resources Research, 19-30.
Mueggler, W. a. (1958). Effects on Associated Species of Burning, Rotobeating, Spraying and Railing Sagebrush. Journal of Range Management, 11: 61-66.
Natural Resouces Conservation Service. (2007). USDA Plants Database. Retrieved from http://plants.usda.gov/java/
Natural Resouces Conservation Service. (n.d.). USDA Plants Database. Retrieved from http://plants.usda.gov/java/
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Paolo Sioli. (1883). Historical Souvenir of El Dorado County, California: With Illustrations and Biographical Sketches of Its Prominent Men & Pioneers. Paolo Sioli, p. 118.
Rosentrater, R., & M. Bowker, a. J. (2007). A Field Guide to Biological Soil Crusts of Western U.S. Drylands. Denver, Colorado: U.S. Government Printing Office.
Sommers, J. (1994). Green River Drift- A History of the Upper Green River Cattle Association. ISBN: 1-56044-280-8.
Stiver, S., Rinkes, E., & Naugle, D. (2010). Sage-Grouse Habitat Assessment Framework. Unpublished, 100-106.
Stringham, T., Kreuger, W., & Shaver, P. (2003). State and transition modeling: an ecological process approach. Journal of Range Management, 56(2): 106-113.
Tanner, R. L. (2016, May 25). Leasing the Public Range: The Taylor Grazing Act and the BLM. Retrieved from WyoHistory.org: http://www.wyohistory.org/encyclopedia/leasing-public-range-taylor-grazing-act-and-blm
USDI, B. o. (2015). Allotment files. Rock Springs, WY: unpublished.
Winward, A. (2007). Boulder, Squaretop Area Field Notes. Unpublished.
Wright, H. A. (1982). Fire ecology: United States and southern Canada. New York, NY: John Wiley & Sons, Inc.
Wyoming Wildlife Consultants, LLC. (2009). Greater Sage-Grouse Focused Herbaceous Monitoring of Moxa Arch Sagebrush Vegetation Treatments. Kemmerer, WY: Bureau of Land Management.

Approval

Scott Woodall, 9/05/2018