PERMFILE61358 - Laserfiche WebLink

Home Browse Search

42.04 APPLICATION FOR PERMIT FOR SIIRFACE OR UNDERGROIIND MINING ACTIVITIES -- MINIMUM REQUIREMENTS FOR INFORMATION ON ENVIRONMENTAL RESOURCES. L 2.04,10 Vegetation Information. (COnt'd,) (4) (Cont'd.) Pinyon-Juniper: The pinyon-juniper zone is found at lower el- evations mainly below 8,000 feet) between the Orchard Valley and Orchard Valley West Mine sites and State Highway 133, on the south and west exposures. The transition zone extends from about 6,500 feet to 8,000 feet near the Orchard Valley Mine and is characterized by dense to widely scattered pinyon and juniper trees separated by a sparse to thick understory of shrubs such as serviceberry, Gambel oak, mountain mahogany, snowberry, skunkbush, and squacaapple. Rig sagebrush, bitter- brush, and mormon tea are scattered in the transition zone on the relatively drier sites. Northern and northeastern slopes in the transition zone tend toward the mountain brush type, having nearly pure stands of shrubs and widely scattered juni- pers. Other areas resemble the pinyon-juniper community ex- cept for the thick undergrowth of shrubs. The herbaceous un- derstory in the transition zone is sparse, consisting of cheatgrass, western wheatgrass, Fendler bluegrass, and forbs such as lambstongue grounsel and bedstraw. Additionally, a few large barren areas occur in the pinyon-juniper zone near . or on the crowns of the ridges. These sites are mostly bare ground and the only vegetation is widely dispersed forbs com- mon to such disturbed arid areas. Sagebrush: The sagebrush type is present above the Orchard Valley Mine site and is typical of the mountain parks and val- ley sagebrush. Big sagebrush is the main component of this zone, while black sagebrush and silver sagebrush are of lesser importance. The annual precipitation of the zones is 15 inches per year or less. They are differentiated chiefly by altitude and accompanying vegetation types. The sagebrush of the mountain parks and valleys is present in the Orchard Valley permit area, where it occurs mainly between 7,500 and 9,000 fee[. The mountainous sagebrush type adjoins moist meadows of drainages at its lower limit and, most com- monly aspen at its upper limit. The herbaceous understory is not as sparse as in the semidesert sage areas; it consists chiefly of Thurber's fescue, western yarrow, American vetch, and skyrocket gilia. Shrubs interspersed in the mountain sagebrush type are mountain snowberry, antelope bitterbrush, and Douglas rabbitbrush. . Revised 08/01/84 Revised 10/12/86 Revised 10/01/87 73