Physiographic features

This site occurs on gentle to steep, concave mountain slopes and canyons slopes. Slopes vary from 4 to 60 percent, but are predominately 20 to 60 percent. It occurs on all aspects, but mostly north and east. Elevations range from 5000 to 7500 feet (1525 to 2300 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 of this site are very deep, well drained, silt loam and loam. The surface layer is a thick dark colored due to the high organic material. They are underlain by medium textured layers that may contain gravel and cobbles. Some soils may have lime horizons below 50 inches, but the overlying soil is usually non-calcareous. Intake rate is moderate and water movement through the soil is moderate. Roots readily penetrate the soil. These soils have a moderate available water holding capacity (AWC). Rock fragments are variable throughout the profile, but are less than 35 percent by volume. Under proper management, these soils have little surface runoff and slight to no erosion. The soils are characterized by a xeric soil moisture regime and a cryic soil temperature regime.

Soil Series Correlated to this Ecological Site


Dranburn
Moonlight
Robin

Table 4. Representative soil features

Animal community

Wildlife Interpretations.

Animal Community – Wildlife Interpretations

Mule deer and elk are large herbivores using this site. The rangeland 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, and mountain bluebirds. Encroachment of noxious and invasive plant species (cheatgrass and rush skeletonweed) 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 artificial water catchments and springs.

State 1 Phase A –Rocky Mountain Maple/ Common Chokecherry/ Mountain Brome Reference Plant Community (RPC) This plant community provides a diversity of grasses, forbs, shrubs, and trees 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. The diverse vertical structure offers habitat for many bird species including mountain bluebird, rock wren, grouse, and flycatchers. The plant community provides important forage for mule deer and elk in the spring, fall, and winter. Chokecherry is a preferred browse for mule deer and elk. Chokecherry fruit is preferred food for many birds and small mammals. The site provides thermal cover and young of year cover for mule deer and elk. A small mammal population including golden-mantled ground squirrels, jackrabbits, deer mice, and Great Basin pocket mice would utilize this plant community.

State 1 Phase 1.2 – Rocky Mountain Maple/ Common Chokecherry Plant Community: This phase has developed due to fire return interval being much longer than normal and/or improper grazing management. An increase in forbs and shrubs to the plant community would result in a similar insect and reptile community as in Sate 1 Phase 1.1. Bird species utilizing the site would be similar to those in State 1 Phase 1.1. Mule deer, elk, and moose would frequent this site. The site would provide thermal cover and young of year cover for large mammals. A small mammal population including golden-mantled ground squirrels, jackrabbits, deer mice, and Great Basin pocket mice would utilize this plant community.

State 1 Phase 1.3- Mountain Brome/ Slender Wheatgrass/ Blue Wildrye Plant Community: This phase has developed due to fire. The plant community, dominated by herbaceous vegetation with sparse shrub and tree cover provides less vertical structure for animals. Insect diversity would be reduced with the loss of most shrubs, but a native forbs plant community similar to that of State 1 Phase 1.1 would still support select pollinators. An increase of mountain snowberry would add spring and summer pollinator habitat to the site. Until mountain maple and mountain snowberry are established, diversity and populations of reptiles would decline. This plant community provides limited brood-rearing habitat for sage-grouse if site is adjacent to sagebrush cover. The dominant herbaceous vegetation improves habitat for grassland avian species (horned lark and western meadowlark). Mountain snowberry would provide good forage for mule deer and elk. Winter habitat for mule deer and elk would be reduced or eliminated with the loss of rocky mountain maple and common chokecherry. Small mammal diversity and populations would be similar to that in State 1 Phase 1.1 and 1.2. The fruit of mountain snowberry provides desirable food for ruffed grouse, magpies, and small mammals.

State 1 Phase 1.4 – Douglas Fir Plant Community: This plant community is the result of fire return intervals being much longer than normal. The reduced shrub and herbaceous understory results in lower diversity and numbers of insects. The reptile community will be similar to that in State 1 Phase 1.1, and includes sagebrush lizard and western rattlesnake. The reduced diversity of insects and understory cover may reduce quality of food and cover for reptile populations. As Douglas fir increases, habitat cover for shrub dependant birds will decline and the bird species dependant on forest habitat will increase. Over time bird species may include hairy woodpeckers, flickers, jays, forest grouse, and mountain chickadee. Quality of winter forage for mule deer and elk is reduced due to the loss of vigor and production of rocky mountain maple and common chokecherry. As Douglas fir encroachment occurs, the site will continue to provide thermal and young of year cover for large mammals. A small mammal population including golden-mantled ground squirrels, jackrabbits, deer mice, and Great Basin pocket mice may utilize this plant community.

State 2 – Annuals/ Forbs: This plant community is the result frequent fire and/or improper grazing management. The site offers limited horizontal and vertical structure for habitat. Insects, birds, and mammals described in phases above would not be supported in this state. Big game animals may utilize the site in early spring when invasive annuals are more palatable. Hunting success of birds of prey would increase due to poor cover conditions provided for small mammals.


Grazing Interpretations.

It is also well suited for livestock use in the summer and fall. If brush becomes dense, it may limit livestock movement.
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 in this site are mostly grouped into hydrologic group B. They have moderately low runoff potential.

Recreational uses

The site has high value of hunting, hiking, photography, and some limited opportunities for camping and picnicking.

Wood products

none.

Other products

none.

Other information

Field Offices

American Falls, ID
Blackfoot, ID
Burley, ID
Driggs, 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.
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, Agricultural Research Service; Interpreting Indicators of Rangeland Health. Technical Reference 1734-6; Version 4-2005.

Approval

Kendra Moseley, 9/23/2020