2009-12-16_REVISION - M1980178 - Laserfiche WebLink

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The existing vegetation communities within the permit boundary are shown on maps that can be found on the following pages. All vegetation communities on the Site are associated with a single soil unit, the very stony Northrim- Garber -Trag complex, 3 to 25 percent slopes. • Pinyon- juniper woodland (approximately 22 acres). The primary plant community on the Site is native pinyon - juniper woodlands, co- dominated by Utah juniper (/uniperus osteosperma) and pinyon pine (Pinus eduiis) less than approximately 20 feet in height. Tree density and degree of canopy closure (15 to 75 percent) varies with slope and aspect. Shrub understory species composition and densities also vary with slope, aspect, and soil moisture regimes. In rocky areas and on relatively steep slopes, the woodlands are relatively open and understory shrubs and herbaceous vegetation is sparse. On deeper soils and gentler slopes, the understory is typically denser and more stratified, and includes big sagebrush (Artemesia tridentata) or Utah serviceberry (Ameianchier utahensis). Native grasses include Indian ricegrass (Achnatherum hymendoides), needle - and- thread (Hesperostipa comata), and galletta (Hi /aria jamesii). Native forbs and sub - shrubs include penstemon (Penstemon sp.), scarlet gilia (ipomopsis sp.), bladderpod (Physaria sp.), pricklypear (Opuntia sp.), broom snakeweed (Gutierrezia sarothrae), and various other small woody asters. Weed species present in this community include cheatgrass (Bromus tectorum) and various annual mustards. According to USDA, such woodlands can produce an estimated 7 cords per acre in a stand in which the tree trunks have an average diameter of 5 inches at a height of one foot. • Cleared pinyon- Luniper woodland (approximately 5 acres). This vegetation community exists mostly on the west parcel of the Site, where the applicant is storing equipment and materials. Dominant vegetation consists of big sagebrush, broom snakeweed, and a variety of common non - native annual and native perennial grasses. Herbaceous rangeland (approximately 1.5 acres). This vegetation community is on the east parcel, and is dominated by a variety of non - native and native grasses and forbs. The USDA non- irrigated land capability classification at the Site is 6e (soils with severe limitations that make them general unsuitable for cultivation and that restrict their use mainly to pasture, rangeland, forestland, or wildlife habitat). Therefore, reclaimed land use will initially be rangeland, with an estimated average production of less than 500 pounds per acre per year (air -dry) and a carrying capacity of approximately 20 cow -calf pairs grazing approximately 4 weeks during the growing season. Following succession by native shrubs such as big sagebrush and broom snakeweed, the land will eventually revert to wildlife habitat dominated by pinyon- juniper woodlands.