2018-11-26_PERMIT FILE - M2018036

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"Historical Range of Variability for Forest Vegetation of the National Forests of the Colorado Front Range";Thomas T. Veblen,Joseph A. Donnegan; USDA Forest Service, Rocky Mountain Region, Golden, CO 80401 A brief discussion of local vegetation that may be present within the Affected Area follows (excerpted from "Plant Communities of the Pike and San Isabel National Forests in South- Central Colorado", revised September 2011, as referenced above): The Ten Percenter Claim, and therefore the Affected Area falls within the Montane vegetation zone. "This zone generally occurs between 7,500-and 9,000-feet elevation, depending on slope exposure. Ponderosa pine forests, often with intermingled meadows of Arizona fescue and other bunchgrasses, dominate the lower montane zone. Douglas-fir forests occupy high- elevation sites and cool slope positions (north and east aspects). At the upper edge of this zone, lodgepole pine, quaking aspen, or spruce-fir forests are occasionally found. Groves of narrowleaf cottonwood occur along low-elevation waterways; with increasing altitude,they are gradually replaced by blue spruce forest. The montane zone has a rich diversity of plant communities. As with other vegetation zones, all of the major montane conifer species can function in either a seral or climax capacity. Ponderosa Pine Plant Communities Ponderosa pine is characteristic of low-elevation sites with moderately deep soils, low to moderate slope gradients, and high-energy aspects (slopes receiving abundant amounts of solar radiation). This conifer is the climax tree species over much of the lower portion of the montane zone, and it is successional to more shade-tolerant conifers on many upper-montane sites. Low-elevation ponderosa pine communities commonly have an herbaceous undergrowth with Arizona fescue, mountain muhly, blue grama, little bluestem, sun sedge, and fringed sage present in varying proportions. Geraniums (Parry and Fremont), flexile milkvetch, western yarrow, showy crazyweed, asters, and lanceleaf bluebells are frequent undergrowth forbs. Bearberry, wax currant, cliff Jamesia, true mountain-mahogany, mountain snowberry, and Parry rabbitbrush are common undergrowth shrubs. Shrubby cinquefoil is occasionally plentiful on lower-montane sites when they have been overgrazed or experienced significant soil erosion. Stands with an open ponderosa pine overstory and a fescue-muhly under-growth are late-seral or sub-climax plant communities. Continued plant succession on these areas will eventually result in a denser pine overstory and an in-crease in shade-tolerant undergrowth plants, especially shrubs or sub-shrubs such as bearberry and common juniper.