The U.S. Sheep Experiment Station is located in the upper Snake River plain at the foothills of the Centennial Mountains, approximately six miles north of Dubois, Idaho, which is the Clark County seat.  Clark county contains 1,765 square miles of land and has a population of approximately 980 persons, approximately 500 of whom live in Dubois.  The USSES is the second largest employer in Clark County. 

Headquarters for the USSES is located within a two-hour drive of Grand Teton and Yellowstone National Parks.  The Continental Divide Trail crosses USSES land in the Centennial Mountains of Montana.  

The USSES has research land in two states: 27,930 acres of ARS land at Headquarters, which has office, laboratory, animal, equipment, and residential buildings, dry-lot facilities for research throughout the year, lambing facilities, and lands used for spring and autumn grazing and rangeland research; approximately 16,600 acres of [unsurveyed] ARS land in the Centennial Mountains of Montana, which is used for summer grazing and rangeland research; 2,600 acres of ARS land at the Humphrey Ranch in Idaho, which is near Monida, Montana, has animal facilities and equipment buildings, and is used for spring, summer, and autumn grazing and rangeland research; and 1,200 acres of ARS land at the Henninger Ranch near Kilgore, Idaho, which has animal facilities and is used for summer grazing and rangeland research. The lands range from approximately 4,800 feet to nearly 10,000 feet in elevation, with average annual precipitation that ranges from approximately 10 inches in the Snake River plain to nearly 21 inches in the Centennial Mountains.  Because of its diverse geography, USSES lands contain subalpine meadow, foothill, sagebrush steppe, and desert shrubland ecosystems.  This diversity provides unparalleled research opportunities within ARS.

The USSES currently has approximately 3,000 mature sheep, plus attendant young sheep of various ages.  Including mature ewes and ewe lambs, lambing rates are approximately 170%, and weaning rates are approximately 145%.  The total number of sheep soon after the end of the lambing period is approximately 6,500.  The numbers of mature and young sheep retained vary according to research needs.  Sheep in excess of those needed for hypothesis-driven research are not retained.  Sheep harvest most of their feed through grazing.  The numbers of sheep are not allowed to approach the carrying-capacity of the land.  Harvested feeds (e.g., alfalfa hay, barley straw, small grains, corn, and various by-products) are used to formulate balanced diets to feed the sheep when they are in dry-lots.

Currently, there are 27 permanent, full-time employees at the USSES: 25 ARS and two University of Idaho employees.  In addition, the USSES has one postdoctoral fellow.The other employees include high school interns, undergraduate interns, graduate students, and intermittent general duty employees.  The USSES has a strong commitment to introducing students from underrepresented groups to agricultural research.  The USSES has an allocation for six scientists, including the research leader.  Currently at the USSES, two ARS scientist and three ARS technician positions are open.

The USSES mission falls within the bounds of USDA, ARS, National Program (NP) 101, Food Animal Production (70%), and NP 205, Rangeland, Pasture, and Forages (30%).  National Programs are described at http://www.ars.usda.gov/research/programs.htm.  To contribute to USDA, ARS, National Programs and accomplish the USSES mission, USSES scientists address problems defined in the Reproductive Efficiency; Genetic Improvement; Nutrient Intake and Use; Growth and Development; and Product Quality components of the NP 101 Action Plan and problems defined the Ecosystems and Their Sustainable Management; Grazing Management: Livestock Production and the Environment; and Integrated Management of Weeds and Other Pests components of the NP 205 Action Plan.  Because of the connectivity among the National Programs and their components, a single experiment at the USSES may contribute to multiple components of NP 101 and NP 205.  This feature of the National Programs and USSES programs will lead to an understanding of the interactions between sheep and the environments in which they are produced that can be used to improve sheep production systems and ensure the sustainability of grazing land ecosystems.