Physiographic features

This site occurs on foothills, hillslopes and canyon walls. Slopes range from 30-65 percent. It occupies south and west aspects. Elevations range from 3000 to 6000 feet (900-1850 meters).

Table 2. Representative physiographic features

Climatic features

The elevation of MLRA 10 ranges from 1791 feet to 9236 feet, with a mean of 4602 feet. Overall, elevation increases from west to east. However, average annual precipitation decreases from west to east, ranging from 16.59 inches to 22.17 inches, with a mean of 19.56 inches, based on 7 long term climate stations throughout the MLRA. In general, precipitation peaks in December and January, with a steady decline to a low in July and August, then a steep increase during the autumn months. Most of the winter precipitation falls as snow, and maximum annual snowfalls of up to 82 inches have been recorded.
There is considerable variation in temperature throughout the year. Temperatures as low as -52° Fahrenheit and as high as 117° Fahrenheit are on record. Some areas have recorded the occurrence of more than 50 days with temperatures above 90° Fahrenheit. The average maximum annual temperature is 63 degrees F, while the average minimum temperature is 36.2 degrees F.The frost-free period can range from 128 to 152 days, while the freeze-free period can be from 164 to 189 days.
Both the average morning and average afternoon relative humidity values are lowest in July and August, and are below the national average. The number of clear, sunny days peaks during this same period, and is higher then the national average. During the Spring and Summer months high-intensity convective thunderstorms are not unusual.

Table 3. Representative climatic features

Influencing water features

This site is not influenced by adjacent wetlands, streams, or run-on.

Soil features

The soils supporting this site are moderately deep or very deep coarse sandy loams. They are somewhat excessively to excessively drain, with moderately rapid or rapid permeability. Available water capacity is very low or low. Runoff is low to medium. The soil surface is inherently unstable and is subject to trampling damage by hoof and foot traffic. These soils are characterized by a xeric soil moisture regime. Soil temperature regime is mesic.

Soil Series Correlated to this Ecological Site -

Olaton Roney Schiller Shimo

Table 4. Representative soil features

Animal community

Wildlife Interpretations.

Animal Community – Wildlife Interpretations

This rangeland ecological site provides diverse habitat for many native wildlife species. Habitat is provided for resident and migratory animals including western toad, sagebrush lizard, western rattlesnake, shrews, bats, jackrabbits, ground squirrels, mice, coyote, red fox, badger, sage-grouse, Ferruginous hawk, prairie falcon, horned lark and western meadowlark. The diverse shrub cover provides suitable habitat for brewer’s sparrow, sage sparrow, sage grouse, and sage thrasher. In some areas encroachment of noxious and invasive plant species (cheatgrass, Medusahead) can replace native plant species which provide critical feed, brood-rearing and nesting cover for a variety of native wildlife. Mule deer and elk utilize the site during spring, summer and fall for food and cover. The steep slopes and snow accumulation reduces value of site for winter food for deer and elk. Water features are sparse provided by seasonal streams, artificial water catchments and springs.

State 1 Phase 1.1 - Foothills Big Sagebrush/ Antelope Bitterbrush/ Bluebunch Wheatgrass/ Sandberg Bluegrass/ Thurber’s Needlegrass Reference Plant Community (RPC): This plant community provides a diversity of grasses, forbs and shrubs used by native insect communities that assist in pollination. The reptile and amphibian community is represented by leopard lizard, short horned lizard, sagebrush lizard, western skink, western rattlesnake, western toad, boreal chorus frog and northern leopard frog. Amphibians are associated with springs and isolated water bodies adjacent to this plant community. Spring developments that capture all available water would preclude the use of these sites by amphibians. Shrub-steppe obligate avian species include the Brewer’s sparrow, sage sparrow, sage thrasher and sage-grouse. Critical habitat (lek sites, nesting areas, winter cover and food) for sage-grouse is provided throughout this ecological site. The plant community supports the needs of large mammals (mule deer and elk) providing food and cover in the spring summer and fall. Antelope bitterbrush is preferred browse for mule deer. A diverse small mammal population including golden-mantled ground squirrels, chipmunks and yellow-bellied marmots would utilize this plant community. The deer mouse is the primary vector for planting bitterbrush seed.

State 1 Phase 1.2 – Foothills Big Sagebrush/Sandberg Bluegrass/ Bottlebrush Squirreltail Plant Community: This phase has developed due to the lack of fire and improper grazing management. An increase in canopy cover of sagebrush contributes to a sparse herbaceous understory. Grasses, forbs and shrubs, are used by native insects that assist in pollination but the reduced herbaceous understory results in lower diversity and numbers of insects. The reptile community is represented by leopard lizard, short horned lizard, sagebrush lizard, western skink and western rattlesnake. Diversity and populations of the reptile community would decline with a reduced understory and associated loss of invertebrate habitat. Spring developments that capture all available water would preclude the use of these sites by amphibians. Key shrub-steppe obligate avian species include Brewer’s sparrow, sage sparrow, sage thrasher and sage-grouse. Reduced herbaceous understory is a key factor in limiting the use of this plant community by avian species. Critical habitat (lek sites, nesting areas, winter cover and food) for sage grouse is limited due to a less diverse herbaceous plant community. The plant community has reduced forage value for mule deer and elk due to poor herbaceous understory and loss of antelope bitterbrush. A diverse small mammal population including golden-mantled ground squirrels, chipmunks, deer mice and yellow-bellied marmots would utilize the habitat. The deer mouse is the primary vector for planting bitterbrush seed.

State 1 Phase 1.3 - Bluebunch Wheatgrass/ Sandberg Bluegrass/ Bottlebrush Squirreltail Plant Community: This plant community is the result of fire. The plant community, dominated by herbaceous vegetation with little to no sagebrush or antelope bitterbrush reduces vertical structure for wildlife. Insect diversity would be reduced. A diverse native forb plant community similar to Phase 1.1 would still support select pollinators. An increase in rabbitbrush would provide fall pollinator habitat. Reptile use including short horned lizard, sagebrush lizard and western rattlesnakes would be limited due to the absence of sagebrush and antelope bitterbrush. The dominance of herbaceous vegetation, increase in rabbitbrushes and loss of sagebrush and antelope bitterbrush canopy cover would severely limit use of these areas for nesting by Brewer’s sparrow, sage sparrow, sage thrasher, and sage-grouse. This plant community provides limited brood-rearing habitat for sage-grouse when sagebrush cover is adjacent to the site. Sage-grouse would not use the area for winter habitat. The dominant herbaceous vegetation improves habitat for grassland avian species (horned lark and western meadowlark). Mule deer and elk forage use would be seasonal (early spring through fall) but the site would offer little thermal cover and young of year cover. The populations of small mammals would be dominated by open grassland species like the Columbian ground squirrel.

State 2 –Sandberg Bluegrass/ Cheatgrass/ Medusahead Rye Plant Community: This plant community is the result of continued improper grazing management and/or frequent fire. Vertical structure is provided by rabbitbrushes and horsebrush. Insect diversity and populations would be reduced with the loss of forbs and change in dominant shrub species. Vertical structure is present but the reduced insect community will reduce quality of reptile habitat. This plant community does not support the habitat requirements for sage-grouse and provides limited habitat for sage thrasher, Brewer’s sparrow or sage sparrow. Birds of prey including hawks and falcons may range throughout these areas looking for prey species. Large mammals may utilize the herbaceous vegetation in the early part of the year when the invasive annuals (cheatgrass) are more palatable. At other times of the year large mammals would not regularly utilize these areas due to poor food and cover conditions. Small mammal populations and diversity would be reduced due to less favorable understory vegetation and reduced insect populations.





Grazing Interpretations.

This site is suitable for late spring, summer, and fall grazing. The steeper slopes will limit livestock movement. Excessive trailing of livestock should be avoided to minimize erosion on the slopes.

Estimated Initial Stocking Rate
This site is suitable for late spring, summer, and fall grazing. The steeper slopes will limit livestock movement. Excessive trailing of livestock should be avoided to minimize terracette development and erosion on the steeper slopes.
Estimated initial stocking rate will be determined with the landowner or decision-maker. They will be based on the inventory which includes species, composition, similarity index, production, past use history, season of use, and seasonal preference. Calculations used to determine estimated initial stocking rate will be based on forage preference ratings.

Hydrological functions

No data.

Recreational uses

This site provides recreational opportunities for hunting, hiking, photography, and horseback riding.

Wood products

None.

Other products

None.

Other information

Field Offices

Weiser, ID
Emmett, ID
Mountain Home, ID
Meridian, ID
Cascade, ID

Inventory data references

Information presented here has been derived from NRCS clipping and other inventory data. Also, field knowledge of range-trained personnel was used. Those involved in developing this site description include:

Dave Franzen, co-owner, Intermountain Rangeland Consultants, LLC
Jacy Gibbs, co-owner, Intermountain Rangeland Consultants, LLC
Jim Cornwell, Range Management Specialist, IASCD
Brendan Brazee, State Rangeland Management Specialist, NRCS, Idaho
Leah Juarros, Resource Soil Scientist, NRCS, Idaho
Lee Brooks, Range Management Specialist, IASCD

Other references

Hironaka, M., M.A. Fosberg, A. H. Winward. 1983. Sagebrush-Grass Habitat Types of Southern Idaho. University of Idaho, Moscow, Idaho. Bulletin Number “35”.
USDA Forest Service, Rocky Mountain Research Station. 2004. Restoring Western Ranges and Wildlands. General Technical Report RMRS-GTR-136-vols. 1-3.
USDA, NRCS.2001. The PLANTS Database, Version 3.1 (http://plants.usda.gov.). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.
USDA, Forest Service, Fire Effects Information Database. 2004. www.fs.fed.us/database.
USDI Bureau of land Management, US Geological Survey; USDA Natural Resources Conservation Service, Agricultural Research Service; Interpreting Indicators of Rangeland Health. Technical Reference 1734-6; Version 4-2005.

Approval

Kendra Moseley, 9/23/2020