. Vegetation of Oregon and Washington. Botany Oregon Ecology; Botany Washington (State) Ecology. 30. Figure 115.—Mountain meadows are common on gentle topography along and near the heads of stream courses in the Abies grandis Zone; they constitute an im- portant grazing resource. are Festuca rubra, Carex spp., Juncus balticus, Aster occidentalis, Polygonum bistortoides, Trifolium spp., and Senecio spp. Most Deschampsia meadows have been overgrazed by domestic livestock (fig. 115) and have deteriorated into other kinds of communities. Reid and Pickford (1946) rec- ognized four major steps in de
. Vegetation of Oregon and Washington. Botany Oregon Ecology; Botany Washington (State) Ecology. 30. Figure 115.—Mountain meadows are common on gentle topography along and near the heads of stream courses in the Abies grandis Zone; they constitute an im- portant grazing resource. are Festuca rubra, Carex spp., Juncus balticus, Aster occidentalis, Polygonum bistortoides, Trifolium spp., and Senecio spp. Most Deschampsia meadows have been overgrazed by domestic livestock (fig. 115) and have deteriorated into other kinds of communities. Reid and Pickford (1946) rec- ognized four major steps in deterioration: (1) perennial grass or climax, (2) mixed grass and weed (fig. 117), (3) perennial weed, and (4) annual weed. Serious erosional problems are associated with these changes in community composition. Major dominants in the peren- nial weed stage are Senecio spp., Achillea mil- lefolium var. lanulosum, Wyethia spp., Poten- tilla spp., Aster occidentalis, Taraxacum offic- inale, and Poa pratensis. The annual weed stage is characterized by Bromus mollis, Muh- lenbergia filiformis, Polygonum douglasii, and Madia spp. Development of climax vegetation from these deteriorated communities is usual- ly extremely slow, even if grazing is complete- ly eliminated. "TSUGA HETEROPHYLLA" ZONE Figure 116. —Deschampsia caespitosa, a perennial grass, dominates mountain meadow communities in good Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Franklin, Jerry F. cn; Dyrness, C. T. Portland, Or. : Pacific Northwest Forest and Range Experiment Station, U. S. Dept. of Agriculture
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