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dasystachya) each contributed more than one-fifth of this total. Sandberg bluegrass (Poa secunda), beardless bluebunch wheatgrass (Pseudoroegneria spicata ssp. inermis), bluebunch wheatgrass (Pseudoroegneria spicata ssp. spicata), green needlegrass (Nassella viridula), mountain bent (Agrostis variabilis), Agassiz bluegrass (Poa agassizensis), and Canada bluegrass (Poa compressa) were present in measurable quantities. Introduced perennial cool season grasses accounted for 28.0 percent of total vegetation cover. Russian wildrye (Psathyrostachys juncea) contributed more than two-thirds of this total. Desert wheatgrass (Agropyron cristatum ssp. desertorum) accounted for more than one-quarter of this total. Intermediate wheatgrass (Thinopyrum intermedium), meadow brome (Bromopsis riparius), and smooth brome (Bromopsis inermis) made relatively minor contributions. Cicer milkvetch (Astragalus titer), an introduced perennial forb, contributed 10.2 percent of total vegetation cover. Native perennial (orbs accounted for 8.3 percent of total vegetation cover. Western yarrow (Achilles lanulosa), two- groove milkvetch (Astragalus bisulcatus), blue flax (Adenolinum lewisii), hoary tansyaster (Machaeranthera canescens), Rocky Mountain penstemon (Penstemon strictus), and Pacific aster (Virgulasterascendens) each contributed to measured cover values. Native shrubs accounted for 7.6 percent of total vegetation cover. Big sagebrush (Seriphidium tridentatum) accounted for more than four-fifths of this total. Rubber rabbitbrush (Chrysothamnus nauseosus), alkali sagebrush (Seriphidium arbusculum ssp. longilobum), and silver sagebrush (Seriphidium canum) contributed the balance. Six other species of native shrubs were present but did not contribute to measured cover values. Six species of native annual and biennial forbs and eight species of introduced annual and biennial forbs were present but did not contribute measurably to cover values. Introduced annual grasses, native perennial warm season grasses, native subshrubs, and lichens were each represented by one species and did not contribute measurably to cover values either. Total vegetation cover was 23.0 percent. Standing dead, litter, bare soil, and rock averaged 2.4, 32.2, 42.0, and 0.5 percent respectively. Species density averaged 17.9 species per 100 sq. m. Production (Table 2) Total annual production in this area averaged 729.8 pounds per acre. Perennial cool season grasses were the major component of this production. Native perennial cool season grasses contributed 49.6 percent (362.2 Ib/acre) of all production and introduced perennial cool season grasses contributed 35.7 percent (260.5 Ib/acre) of all production. Western wheatgrass and sheep fescue were the most important native cool season grasses and accounted for more than two-thirds of this total. Eleven other species made more minor contributions. Russian wildrye was the dominant introduced perennial grass and comprised more than one-half of this total. Desert wheatgrass accounted for nearly one-third of this lifeform's production. Intermediate wheatgrass and smooth brome accounted for the balance. Native perennial forbs comprised 8.3 percent (60.7 Ib/acre) of all production. Showy fleabane (Erigeron speciosus), blue flax, western yarrow, and hoary tansyaster were the most dominant species in this lifeform. Four other species contributed the balance. Native shrubs accounted for 2.7 percent (19.6 Ib/acre) of all production. Big sagebrush contributed nearly two-thirds of this total. Wood's rose (Rosa woodsi~), rubber rabbitbrush, and Douglas rabbitbrush (Chrysothamnus viscidiflorus) accounted for the balance. The introduced perennial forbs, titer milkvetch, Canada thistle, and dandelion (Taraxacum officinale), accounted for 2.4 percent (17.8 Ib/acre) of all production. The native subshrubs, fringed sage (Artemisia frigida) and Greene rabbitbrush (Chrysothamnus greener), contributed less than one percent (5.4 Ib/acre) of all production. Five species of introduced annual and biennial forbs also accounted for less than one percent (1.8 Ib/acre) of all production. Shrub Density (Table 3) Total woody stem density in this area averaged 1473.8 individuals per acre. Native shrubs contributed 1299.7 woody stems per acre. Big sagebrush accounted for three-fifths of this total. Wood's rose and rubber rabbitbrush combined to contribute nearly one-quarter of this total. Silver sagebrush, winterfat (Krascheninnikovia Janata), prickly rose (Rosa sayr), Douglas rabbitbrush, and tall threetip sagebrush (Seriphidium tripartitum) were present in lesser quantities.