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The reproduction rate of the oak communit~ is very high. <br />• Rates ranged from 17 to 241 trees per 25m and averaged <br />2,072 sapling per acre. Thus it appears that the oaks <br />were colonizing favorable habitats and extending their <br />coverage. <br />The most common shrubs in the oak understory are <br />snowberry and serviceberry. Other shrubs present include: <br />big sage, rabbitbrush, chokecherry, and rose. Total shrub <br />cover (which includes oak as a shrub) averages 108 percent. <br />Oak forms the greater proportion of the canopy cover, <br />71 percent. The percent canopy cover of other shrubs is <br />variable depending on the specific community sampled. <br />snowberry and serviceberry are most common followed by <br />chokecherry. Sagebrush, rabbitbrush and rose are only <br />sparsely present in the community. These shrubs form <br />an understory canopy beneath the oak canopy. serviceberry <br />and chokecherry grow up to three meters in height in some <br />of the sampled stands. Sagebrush and snowberry range <br />from 1 to 2 meters in height while rabbitbrush and rose <br />are 0.5 to 1 meter in height. <br />The herbaceous understory of the oak community consists <br />of 45 species: 36 forbs, 8 grasses and 1 sedge. Total <br />percent vegetation cover averages 41 percent, but ranges <br />from 24 to 47 percent. Graminoids dominate the herbaceous <br />• understory. Elk sedge is present in all sample stands <br />ranging in cover up to 34 percent, and bluegrass with an <br />8 percent cover is also common. Elk sedge is abundant in <br />the dense oak communities, while bluegrass is abundant in <br />the least dense communities. Mountain brome, Ceratochloa <br />marginata; nodding brome, Bromopsis porteri; giant wild-rye, <br />Elymus cinereus; and blue wild-rye, are also frequently <br />present in the oak community. <br />Forb cover is very sparse in the oak community. <br />Thirty-three forbs cover an average 9 percent of the <br />area. In order of their abundance, the most common forbs <br />are yarrow; vetch; bedstraw, Perideridia gairdneri; showy <br />daisy, Erigeron speciosus; goosefoot, Chenopodium gZaucum; <br />Yampa; knotweed, PoZygonum dougZasii; and wild tarragon, <br />Artemisia draouncuZus. <br />An extensive layer of litter (63 percent cover) composed <br />principally of leaves from deciduous shrubs is characteristic <br />to the oak community. Exposed soil (13 percent) and mosses <br />and lichen (0.5 percent) cover little ground area. <br />2.3 Sagebrush-snowberry Community <br />The sagebrush-snowberry community has a scattered <br />• distribution at the study site. This community dominates <br />the areas of deep loam and clay loam soils (Hesperus and <br />Waterino Series Complex) in streamless drainage channels, <br />-10- <br />