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cover comprised of cover by twentyone native perennial forbs. Twenty-three other species were <br />• encountered in the samples but did not contribute measurably to cover. The most abundant <br />native perennial forbs were horsemrnt (Monarch frstulosa var. menthifolia), edible valerian <br />(Valerians edulis), American vetch, and nettle-leaf giant hyssop (Agastache urticifolia). One <br />species of native tree, quaking aspen (Populus tremuloides) was present in the area, contributing <br />2% to total vegetation cover. Nine species of introduced annual and biennial forbs composed 2% <br />of total vegetation cover. Hound's tongue composed the three-fourths of this lifeform total while <br />shepherd's purse (Capsella bursa-pastoris) and twolobe speedwell contributed most of the <br />balance. Bracken fern (Pteridium aquilinum ssp. lanuginosum) contributed 1.6% of total <br />vegetation cover. Native annual and biennial forbs provided 0.3% of total vegetation cover, split <br />in thirds by western rockjasmine (Androsace occidentalis), linearleaf collomia (Collomia linearis), <br />and Douglas knotweed (Polygonum douglasii). <br />Production <br />(Table 17) <br />Herbaceous production averaged 435 Ibs/acre. No alfalfa was present in the Mountain Brush <br />reference area in 2002. <br />Sagebrush Reference Area <br />(Photographs 26, 29, and 30) <br />Cover <br />(Table 18) <br />More than half of total vegetation cover was provided by native shrubs. Big sagebrush and <br />mountain snowberry were in equal parts responsible for virtually all of this cover. Douglas <br />rabbitbrush and chokecherry collectively contributed a small amount. Native perennial cool <br />season grasses produced 30% of total vegetation cover. Greater than half of this amount was <br />provided by Rocky Mountain fescue (Festuca saximontana). Agassiz bluegrass comprised about <br />one-fifth of the lifeform total and thickspike wheatgrass about one-tenth. The balance of <br />measurable cover was contributed by mduntain brome, Nelson needlegrass, slender wheatgrass, <br />Letterman needlegrass, and green needlegrass. Six other species were also present. Sixteen <br />percent of total vegetation cover was composed of native perennial forbs. Nineteen species were <br />observed, nine quantitatively. In order of decreasing abundance, native perennial forbs <br />contributing to over 1 % of total vegetation cover were one-flower woodsunflower, timber <br />milkvetch ,sulphur flower (Eriogonum umbellatum), western yarrow, -showy fleabane (Erigeron <br />speciosus), and Pacific aster. Arrowleaf balsamroot, American vetch, and chokecherry lupine <br />(Lupinus prunophilus) each contributed less than 1 % to total vegetation cover. Timothy provided <br />• all measured cover for the introduced perennial grass lifeform with 0.6% of total vegetation cover. <br />14 <br />