Physiographic features

This site occurs on nearly level to very steep slopes generally ranging in 30 to 60 percent. The aspect is south and west. Elevations range from 4000 to 7500 feet (1200-2273 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 very shallow to moderately deep, well drained (Blackspar is somewhat excessively drained), with impermeable to moderate permeability. Runoff is medium to very high. A clay subsoil limits water and root penetration. The erosion hazard is moderate to very severe by water. The available water capacity is very low to moderate. The surface texture is very cobbly to extremely stony loams and clay loams. Gravels and stones may be present throughout the profile. These soils are characterized by a xeric soil moisture regime (Chilcott and Kunaton are aridic). Soil temperature regime is mesic, frigid or cryic.

Soil Series Correlated to this Ecological Site


Blackspar
Blisshill
Bray
Chilcott
Connet
Day
Dollarhide
Duguesclin
Furshur
Gaib
Gaibson
Gwin
Hobby
Karcal
Kunaton
Ruckles
Schooler
Spaa
Starhope
Stash
Thorncreek
Tschamman
Willho
Winridge
Yutrue

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. The plant community exhibits a diverse mixture of forbs throughout the growing season offering excellent habitat for invertebrates. Mule deer and antelope are the large herbivores using the site. The site provides seasonal habitat for resident and migratory animals including western toad, sagebrush lizard, shrews, bats, ground squirrels, mice, coyote, red fox, badger, sage-grouse, Ferruginous hawk, prairie falcon, horned lark and western meadowlark. Sagebrush obligate avian species including sage-grouse, Brewer’s sparrow, sage sparrow, and sage thrasher utilize these sites on a limited basis due to the low vertical structure of sagebrush, high elevation and associated cold temperatures throughout much of the year. Sage-grouse an area sensitive species, may utilize the low sagebrush plant community as winter, breeding, nesting and brood-rearing habitat. Encroachment of noxious and invasive plant species (cheatgrass and medusahead) in isolated areas can replace native plant species which provide critical feed, brood-rearing and nesting cover for a variety of native wildlife. Water features are sparse provided by seasonal streams, artificial water catchments and springs.

State 1 Phase 1.1 – Low Sagebrush/ Bluebunch Wheatgrass/ Sandberg Bluegrass Reference Plant Community (RPC): This plant community provides a diversity of grasses, forbs and shrubs, used by native insect communities that assist in pollination. An extensive array of forbs is represented throughout the growing season leading to a diverse insect community. Many avian and mammal species utilize this habitat based on the availability of invertebrate prey species. 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. Development of spring sites that collect all available water would exclude amphibian use on these sites. Native shrub-steppe obligate avian species utilizing the habitat include the Brewer’s sparrow, sage sparrow, sage thrasher and sage-grouse. Area sensitive species include sage-grouse which utilize the low sagebrush for winter habitat. Sage-grouse may utilize this plant community for brood-rearing and nesting habitat as well. The plant community provides seasonal forage needs for large mammals including mule deer, antelope, and elk. A diverse small mammal population including golden-mantled ground squirrels, chipmunks and yellow-bellied marmots would utilize this community. Habitat for the pygmy rabbit would be marginal due to the low height and density of sagebrush and stony soils.

State 1 Phase 1.2- 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 or no sagebrush provides less vertical structure for animals. Insect diversity would be reduced but a diverse native forb plant community would still support select pollinators. An increase in rabbitbrushes would provide fall pollinator habitat. The reptiles, short horned lizard and sagebrush lizard would be limited or excluded due to the loss of sagebrush. Amphibian habitat would be tied to permanent spring sites in the area. Development of spring sites that collected all available water would exclude amphibian use on these sites. The dominance of herbaceous vegetation with little sagebrush canopy cover would prevent use of these areas as nesting habitat by Brewer’s sparrow, sage sparrow, sage thrasher, and sage-grouse. This plant community provides limited brood-rearing habitat for sage-grouse when adjacent sagebrush cover is provided. Use as winter cover and winter food by sage-grouse is eliminated. The dominant herbaceous vegetation improves habitat for grassland avian species (horned lark and western meadowlark). Large mammal (mule deer, antelope, and elk) use would be seasonal and the site would offer little thermal cover and young of year cover. Small mammal diversity would be reduced.

State 1 Phase 1.3 – Low Sagebrush/ Sandberg Bluegrass Plant Community:
This plant community is the result of improper grazing management and no fire. An increase in canopy cover of sagebrush results in a sparse herbaceous understory. Native insects assist in pollination but the reduced herbaceous understory results in lower diversity and numbers of insects. The reduction of grasses and forbs in the plant community would reduce the available prey species and cover for the resident reptile species. Amphibian habitat would be tied to permanent spring sites in the area. Development of spring sites that collected all available water would exclude amphibian use on these sites. Key shrub-steppe obligate avian species include Brewer’s sparrow, sage sparrow, sage thrasher and sage- grouse. Critical habitat (winter cover and winter food) for sage-grouse is available. The plant community supports a shorter duration of seasonal forage habitat for mule deer, antelope, and elk. A small mammal population including golden-mantled ground squirrels, chipmunks and yellow-bellied marmots would utilize these areas.

State 2 - Sandberg Bluegrass / Cheatgrass / Medusahead Plant Community:
This plant community is the result of continued improper grazing management and/or frequent fire. The plant community does not support a diverse insect community. The reduced forb and shrub component in the plant community would support a very limited population of pollinators. Most reptilian species are not supported with food, water or cover. This plant community does not support the life requisites for sage-grouse, sage thrasher, Brewer’s sparrow or sage sparrow. Diversity of grassland avian species is reduced due to poor cover and available food. 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. The populations of small mammals would be dominated by open grassland species like the Columbian ground squirrel.

State 3 - Low Sagebrush/ Sandberg Bluegrass / Cheatgrass / Medusahead Plant Community: This plant community is the result of improper grazing management and no fire. An increase in canopy cover of sagebrush results in a sparse herbaceous understory dominated by invasive plant species. Native insect populations and diversity are severely reduced. The reptile population is reduced and represented by leopard lizard, short horned lizard and sagebrush lizard. The reduction of native grasses and forbs in the plant community would reduce the available prey species and cover for these resident reptile species. Key shrub-steppe obligate avian species include Brewer’s sparrow, sage sparrow, sage thrasher and sage- grouse. Their use of these areas will be reduced due to poor understory vegetation and available prey. Critical habitat (winter cover and winter food) for sage grouse is available. The plant community supports a short duration seasonal forage habitat for mule deer, antelope, and elk. A small mammal population including golden-mantled ground squirrels, chipmunks and yellow-bellied marmots utilize these areas.

Grazing Interpretations.

This site is suited for grazing by livestock in spring, early summer, and fall. Early spring grazing should be avoided due to prolonged wetness in the soil.
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

The soils in this site are in hydrologic group C and D.

Recreational uses

Colorful spring and early summer blooming forbs provide excellent opportunities for photography and nature study. Hunting opportunities for pronghorn antelope and sage grouse exist.

Wood products

None

Other products

None

Other information

Field Offices.

Mountain Home, ID
Gooding, ID
Fairfield, ID
Shoshone, ID
Rupert, ID
Arco, 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, Rangeland Management Specialist, IASCD
Brendan Brazee, State Rangeland Management Specialist, NRCS, Idaho
Lee Brooks, Rangeland Management Specialist, IASCD
Leah Juarros, Resource Soil Scientist, NRCS, Idaho

Type locality

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/feis
USDI Bureau of Land Management, US Geological Survey; USDA Natural Resources Conservation Service; Interpreting Indicators of Rangeland Health. Technical Reference 1734-6; version 4-2005.

Approval

Kendra Moseley, 9/23/2020