1999-04-26_PERMIT FILE - M1999051 (2)

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UNITED STATES DEPARTMENT OF AGRICULTURE Soil Conservation Service, Colorado Forest Type Mapping Symbol County February 1976 Woodland Type Description for Pinyon-Juniper 1 . Physiographic Features This woodland association generally occurs at elevations between 5,000 and 7,500 feet above sea level , except that, in the San Luis Valley, the elevation range is 8,000 to 9,000 feet above sea level . This is generally the first woodland type above the natural grasslands. 2. Climatic Features Annual precipitation averages from 12 to 15 inches with an average annual temperature of 49 to 53° F. and frost-free period of 60 to 120 days. 3. Native Vegetation The pinyon-juniper woodland type is a tree plant association and occurs at the lowest elevations of any of the wood- lands in Colorado. At the lower limits, the type becomes almost pure stands of Utah juniper on .the Western Slope and one-seed juniper on the Eastern Slope. In the middle of the range, a mixture of the pinyon pine and juniper occurs and at the upper slopes of this type, pinyon pine tends to become the dominant species of the stand. 4. Assocaited Understory Plants With the wide distribution of the Pinyon- Juniper woodland in Colorado there are major variations in the kinds of plants in the potential plant community. Understory plants of East- ern Colorado show their relationship to the Plains region and its warm-season plants. Western Colorado understory plants reflect the influence of the Intermquntain region where cool-season plants are favored. Grasses in the understory are often the dominant species. Those commonly growing in abundance at different locations include Indian ricegrass, blue grama, muttongrass, western wheatgrass, bluebunch wheatgrass, beardless bluebunch wheatgrass, side-oats grama, and galleta. Grasses growing in less abundance or in sub-dominant positions include needle-and-thread, Junegrass, Scribner needlegrass, squirreltail , sand dropseed, sedges, little bluestem, mountain muhly, three-awn, Sandberg bluegrass and slimstem muhly.