Laserfiche WebLink
f <br />~f, <br />•~ ~~~_ <br />I' <br />~: <br />UNITED STATES DEPARTMENT OF AGRICULTURE '~ y1 <br />Soil Conservation Service, Colorado <br />Technical Guide <br />Section II E <br />RANGE SITE N0. 228 <br />Field Office <br />August 1975 <br />RANGE SITE DESCRIPTION <br />for <br />MOUNTAIN LOAM <br />Land Resource Area: Southern Rocky Mountains (4 S) <br />A. PHYSICAL CHARACTERISTICS <br />1. Physiographic Features <br />.~ L~~ography is mai-%•~ a11~.:vial-colluvial slopes, terraces, fans. <br />or valley positions. Slopes average between 5 to 10$ but can <br />reach 30 to 40$. Elevation ranges from 7000 feet to 9500 feet. - '• <br />• ~^'~- 2. Climatic Features <br />Average annual precipitation is 15 to 20 inches, of which about <br />50$ falls as snow. <br />Optimum growing season for native plants is early spring through - <br />summer. The frost-free period ranges from 30 to 100 days. Mean <br />annual temperature ranges from 70°js to (-) 40°'s F. This site <br />normally has deep snow cover through the winter. - ', <br />3. Native (potential) Vegetation <br />Grass, in association with minor amounts of woody plants such as <br />sagebrush and snowberry and several forbs, accounts for most of <br />the vegetative cover. This site is treeless; however, trees are ' <br />often in the general vicinity. Dominant grasses are Idaho and/or <br />• Arizona fescue, slender wheatgrass, bearded wheatgrass, native <br />bluegrasses, nodding brome, mountain brome, Letterman's needle- <br />grass and pine needlegrass. Mountain muhly and Parry oatgrass <br />are important in some locations. Lupine, geranium, groundsel and <br />bluebells are the principal forbs. With range depletion, sage- <br />brush often becomes dominant. <br />Optimum ground cover is 35~• The following species are most likely <br />to invade this site: cheatgrass, slimstem muhly, three-awn, blue <br />• ~~~ grams, rubberweed, broom snakeweed, tall rabbi[brush, phlox, and ~ ~ . <br />nailwort. <br />