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Setrian 2.04.10
<br />order of dominance, Gambel oak, mountain snowbeny, big sagebrush, fourwing saltbush, skunkbush
<br />sumac, speazleaf buckwheat, cliff fendlerbush, low nbbitbrush, Saskatoon serviceberry, Oregon grape,
<br />mountain mahogany, rubber rabbitbrush, antelope bitterbrush, and woods rose. Grasses and forbs
<br />occur in open areas (12.8 percent of total cover), with Indian ricegrass, native bluegrass, quackgrass,
<br />Letterman needlegrass, basin wildryt:, cheatgrass brome, Japanese brome, western wheatgrass,
<br />beardless bluebunch wheatgrass, and squirreltail as the primary grass species, and prairie sage,
<br />glaucous aster, whitetop, showy daisy, Colorado bedstraw, tailcup lupine, hoary tansy-aster, mules-ear
<br />wyEthia, prairie sunflower, and alyssum as the primary forb species. Hedgehog and pricklypeaz cactus
<br />are ako found sporadically in drier areas.
<br />Total vegetative cover for the Mountain Shmbland community is 55.6 percent, with soil cover of 17.9
<br />percent, litter cover of 20.5 percent, and rock cover of 6.0 percent. Of this total, the following
<br />s~~mrn~~~es relative contributions by vegetation type:
<br />• Tree cover contributes 3.1 percent (Utah juniper - 1.8 percent and Rocky Mountain
<br />juniper - 1.3 percent)
<br />• Shmb and sub-shrub cover contributes 31.8 percent (Gambel oak - 16.1 percent,
<br />mountain snowberry- 5.5 percent, big sagebrush - 1.9 percent, fourwing saltbush - 1.8
<br />percent, skunkbush sumac - 1.3 percent, speazleaf buckwheat - 1.1 percent, cliff
<br />fendlerbush - 0.9 percent, low nbbitbrush - 0.9 percent, Saskatoon serviceberry - 0.7
<br />percent, Oregon grape - 0.6 percent, and other -1.0 percent)
<br />• Perennial and annual grass cover contributes 12.9 percent (cheatgrass brome - 7.4
<br />percent, Japanese brome - 2.6 percent, and other - 2.9 percent)
<br />• Perennial and annual forb cover contributes 7.6 percent (distributed over a large number
<br />of species)
<br />• Cryptogam (mosses and lichens) cover is negligible
<br />Total herbaceous production for the Mountain Shrubland community avenged 494 lbs. per acre, with
<br />grasses contributing approximately 56 percent (276 16s. per acre) and forbs contributing the remaining
<br />44 percent (218 lbs. per acre).
<br />Tree density for the Mountain Shrubland community averaged 31 trees per acre divided between Utah
<br />juniper (17 trees per acre) and Rocky Mountain juniper (12 trees per acre). Shrub density averages
<br />5,849 shrubs per acre, with Oregon grape (1,863 shrubs per acre), Gambel oak (1,545 shrubs per
<br />acre), and mountain snowberry (1,179 shrubs per acre) dominant.
<br />Species diversity for the Mountain Shrubland community is limited; with a species diversity index of
<br />only 1.22. Forty-seven species contribute to measured cover, but close to 30 percent of the measured
<br />cover comes from only four species (Gambel oak, mountain snowberry, cheatgnss brome, and
<br />Japanese brome). The limited diveaity u a reflection of the dominance of shrubs, the xeric nature of
<br />the east and southeast facing slopes, and the replacement of native species by introduced species.
<br />Plant Species
<br />A total of 135 plant species were identified by the baseline vegetation sampling. This total includes 8
<br />tree, 24 shrub, 23 perennial grass, 2 annual grass, 48 perennial forb, 27 biennial or annual forb, and 3
<br />succulent species. A complete listing of the identified species u included in Baseline Vegetation
<br />Inventory Report (Wes[em Resource Development, 2/82) in Exhibit 2.04-E6, Vegetation
<br />Information. Twenty-four of the identified species are non-native introduced weeds or cultivars. Of
<br />the introduced species only quackgrass and whitetop are considered noxious weeds, although neither
<br />are included in noxious weed listing in the CDMG Noxious Weed Guideline.
<br />PR04 2.04105 Revised August 2000
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