Loamy Glacial Outwash

Description

If ecological retrogression is cattle-induced, desirable grasses will decrease. However, if retrogression is sheep-induced, desirable forbs and shrubs may be reduced. Deterioration of this site caused by continuous grazing by cattle will decrease the percentage of grasses such as Canada bluegrass, muttongrass, needle and thread, Arizona fescue, little bluestem, elk sedge, western wheatgrass and mountain muhly. With the decrease of these plants; blue grama, bottlebrush squirreltail, slimstem muhly, and sun sedge will increase initially along with yellow (small) rabbitbrush, Howard's rabbitbrush, broom snakeweed, and fringed sagewort. Forbs, half-shrubs and shrubs likely to increase include oak brush, granite gilia, northwestern cinquefoil, rose pussytoes, white sagebrush (Louisiana sagewort), and Nebraska lupine. Continued overgrazing will reduce blue grama, needle and thread, and bottlebrush squirreltail, and further increase slimstem muhly, sun sedge, and less preferred forbs and shrubs. Plant species likely to invade include Kentucky bluegrass, cheatgrass, flannel mullein, sleepygrass, crypthanta, and prickly pear cactus.

Basal area (the area of ground surface covered by the perennial vegetation measured one inch above the soil) is approximately 15 percent.

Submodel