Physiographic features

This site occurs on windswept exposed mountain sides and canyon side slopes. The site consists of long narrow bands on ridgetops. Slopes range from 5 to 60 percent generally with a south or westerly aspect. Elevations range from 6500 to 9000 feet (1950 to 2750 meters).

Table 2. Representative physiographic features

Climatic features

MLRA 13, the Eastern Idaho Plateaus, is part of the Northwestern Wheat and Range Region. Its elevation ranges from 4209 to 9331 feet above sea level, with an average elevation of 5787 feet. The average annual precipitation is 16.41 inches, with a range of 13.56 to 18.75 inches, based on ten long term climate stations located throughout the MLRA. A spike in precipitation amount often occurs in late spring, usually in May.
Temperatures vary widely in the MLRA throughout the year. A maximum temperature of 103° Fahrenheit occurred at the McCammon climate station (# 105716; elevation 4770 feet), while a minimum of -41° was recorded at the Kilgore station (#104908). At all stations temperatures throughout the year are usually below the national average. Kilgore also recorded the greatest annual snowfall amount of 217 inches. The average temperature is 41.4 degrees F. with an average high of 55.3 degrees and an average low of 27.5 degrees.
The frost-free period ranges from 64 to 90 days, while the freeze-free period can be 98 to 123 days.

Table 3. Representative climatic features

Influencing water features

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

Soil features

The soils on this site are shallow to deep to fractured bedrock which is generally limestone. They have medium to moderately fine surface textures, mostly sandy loam to loam. Surface textures may range from gravelly to very gravelly and stony to extremely stony. Coarse fragments increase with depth and are approximately 40 percent by volume. Permeability is moderate. The available water holding capacity (AWC) is very low to low, except for cracks in the bedrock which stores water for deep-rooted plants. Erosion is not excessive due to coarse fragments on the surface unless vegetation is depleted and slope increases. The site is characterized by a xeric soil moisture regime and a cryic soil temperature regime.

Soil Series Correlated to this Ecological Site


Middlehill
Povey

Table 4. Representative soil features

Animal community

Wildlife Interpretations.
Animal Community – Wildlife Interpretations

This rangeland ecological site provides habitat for select native wildlife species who can tolerate cold sites, high in elevation, with a sparse plant community. The plant community exhibits a diverse mixture of forbs throughout the short growing season offering habitat for invertebrates. At lower elevations mule deer, pronghorn antelope, and elk are the large herbivores using the site. The site provides seasonal habitat for resident and migratory animals including western toad, sagebrush lizard, shrews, ground squirrels, mice, coyote, red fox, badger, sage-grouse, Ferruginous hawk, prairie falcon, horned lark, and western meadowlark. Sage-grouse is an area sensitive species in this plant community. Encroachment of noxious and invasive plant species (cheatgrass) 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 runoff, artificial water catchments, and springs.

State 1 Phase 1.1 –Black Sagebrush/ Bluebunch Wheatgrass/ Sandberg Bluegrass/ Indian Ricegrass/ Bottlebrush Squirreltail/ Mountain Big Sagebrush Reference Plant Community (RPC) This plant community provides a diversity of grasses, forbs, and shrubs used throughout the growing season by native insect communities that assist in pollination. The reptile and amphibian community is represented by common sagebrush lizard, western rattlesnake, Great Basin spadefoot toad, western toad, 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. Sage-grouse utilize this plant community for nesting, winter food, and cover. The plant community provides forage for mule deer, antelope, and elk in the spring, fall, and winter. A diverse small mammal population including golden-mantled ground squirrels, jackrabbits, deer mice, and Great Basin pocket mice may utilize this plant community. Pika may be present at higher elevations when adjacent to talus slopes.

State 1 Phase 1.2- Black Sagebrush/ Sandberg Bluegrass Plant Community: This plant community is the result of improper grazing management and lack of fire. An increase in canopy cover of sagebrush contributes to a sparse herbaceous understory. The reduced herbaceous understory results in reduced diversity and numbers of insects. The reptile and amphibian community is similar to that identified in State 1 Phase 1.1. The reduction of grasses and forbs in the plant community would reduce the available prey species and cover for these resident reptiles. The quality of nesting and brood rearing habitat for birds would be lowered due to the sparse understory cover. Winter cover and winter food for sage-grouse is available. Reduced understory vegetation would lower spring and fall forage value for deer, antelope, and elk. Winter browse for deer and antelope would still be available at lower elevations. The small mammal population would be similar to the State 1 Phase 1.1 animal community.


State 1 Phase 1.3 – Bluebunch Wheatgrass/ Sandberg Bluegrass Plant Community: This plant community is the result of fire. The plant community, dominated by herbaceous vegetation would provide less vertical structure for animals. Patches of root sprouting shrubs (rabbitbrushes and gray horsebrush) may be present and provide limited vertical structure for wildlife. Insect diversity would be reduced due to less diverse shrub cover, but a native forb plant community would still support select pollinators. Rabbitbrush would add fall pollinator habitat in the future. Habitat quality for reptiles including common sagebrush lizard and western rattlesnake would decline due to the loss of brush cover. Winter cover and winter forage use by sage-grouse is eliminated. The dominant herbaceous vegetation improves habitat for grassland avian species (horned lark and western meadowlark). Large mammal (mule deer, elk, and antelope) use for forage would be limited to herbaceous vegetation in the spring, summer, and fall.

State 2 Phase 2.1 - Black Sagebrush/ Sandberg Bluegrass/ Annuals Plant Community: This plant community is the result of improper grazing management and lack of fire. The reduced herbaceous understory results in reduced diversity and numbers of insects. The reptile and amphibian community is similar to species identified in State 1 Phase A1.1 animal community. The reduction of grasses and forbs in the plant community would reduce the available prey species and cover for these resident reptiles. The quality of nesting and brood rearing habitat for birds would be lowered due to the sparse understory cover. Winter cover and winter food for sage-grouse is available. At lower elevations the reduced understory vegetation would lower spring and fall forage value for deer, antelope, and elk. Winter browse for deer and antelope would be available. The small mammal population would be similar to the State 1 Phase 1.1 animal community.

State 2 Phase 2.2 – Sandberg Bluegrass/ Cheatgrass / Annuals Plant Community: This phase has developed due to improper grazing management from State 1, Phase 1.3 or with improper grazing management and fire from State 2, Phase 2.1. 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. 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. Deer and pronghorn 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 ungulates would not utilize these areas.


Grazing Interpretations:

The suitability of this site for grazing by cattle is limited due stony soils, low production, and a lack of water. This site can be most effectively grazed by sheep in the summer.
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

Soils on this site are in hydrologic group D. The site has high run-off potential especially when the vegetation is removed.

Recreational uses

This site has good values for aesthetics and recreational hiking. The site is located on elevated areas with a view of the valleys and canyons below.

Wood products

none

Other products

none

Other information

Field Offices

American Falls, ID
Blackfoot, ID
Burley, ID
Driggs, ID
Fort Hall, ID
Idaho Falls, ID
Malad, ID
Pocatello, ID
Rexburg, ID
Soda Springs, ID
St. Anthony, ID

Revision Notes: “Previously Approved” Provisional
This Provisional ecological site concept has passed Quality
Control (QC) and Quality Assurance (QA) to ensure that the site
meets the 2014 NESH standards for a Provisional ecological site
description. This is an updated “Previously Approved” ESD that
represents a first-generation tier of documentation that, prior to the
release of the 2014 National Ecological Site Handbook (NESH),
met all requirements as an “Approved” ESD as laid out in the 1997
(rev.1, 2003) National Range and Pasture Handbook (NRPH). The
document fully described the Reference State and Community
Phase in the State-and-Transition model. All other alternative
states are at least described in narrative form. The “Previously
Approved” ESD has been field-tested for a minimum of five years
and is a proven functional document for conservation planning.
The “Previously Approved” ESD does not contain all tabular and
narrative entries as required in the current “Approved” level of
documentation, but it is expected that the “Previously Approved”
ESD will continue refinement toward an “Approved” status.

Site Development and Testing Plan:
Future work, as described in a Project Plan, is necessary to
validate the information in this Provisional Ecological Site
Description. This will include field activities to collect low-,
medium-, and high-intensity sampling, soil correlations, and
analysis of that data. Annual field reviews should be done by soil
scientists and vegetation specialists. The final field review, peer
review, quality control, and quality assurance reviews of the ESD
will be required to produce the final document.

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
Lee Brooks, Range Management Specialist, IASCD
Kristen May, 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”.
Petersen, S.L., 2004. A Landscape-Scale Assessment of Plant Communities, Hydrologic Processes, and State-and-Transition Theory in a Western Juniper Dominated Ecosystem. PhD Dissertation. Oregon State University, Corvallis, Oregon.
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