Physiognomy and Structure: No Data Available

Floristics: This open montane shrubland is dominated by moderate cover of the short shrub Artemisia tridentata ssp. vaseyana (10-50% cover) and the introduced perennial sodgrass Poa pratensis (to 50% cover). The remaining tall- and short-shrub layers provide sparse to low cover and include Amelanchier utahensis, Artemisia cana (2-8% cover), Purshia tridentata, Salix scouleriana, and Symphoricarpos oreophilus. Occasional Populus tremuloides trees are present on one site. The composition of the herbaceous layer varies considerably, both in species richness and in species composition. Other species in the low to moderate (10-30% cover) herbaceous layer tend to be relatively mesic and include graminoids Achnatherum pinetorum, Elymus lanceolatus, Elymus trachycaulus, Festuca idahoensis, Juncus arcticus ssp. littoralis (= Juncus balticus), Koeleria macrantha, Leucopoa kingii, Poa fendleriana, and the non-native perennial Phleum pratense. Forbs include Agastache urticifolia, Achillea millefolium, Artemisia ludoviciana, Balsamorhiza sagittata, Eriogonum umbellatum, Lupinus sericeus, Potentilla sp., and Solidago sp.

Dynamics:  Invasion of non-native Poa pratensis in Artemisia tridentata ssp. vaseyana-dominated shrubland stands is common after disturbance (Johnston 2001). The rhizomatous Poa pratensis forms a sod that is unusually resistant to heavy utilization and trampling by livestock (USDA 1937). It is more tolerant of heavy grazing than native bunch grasses such as Festuca arizonica, Festuca thurberi, and Danthonia parryi (Johnston 2001). The restoration of a native herbaceous community is difficult after depletion by livestock overgrazing (Hironaka et al. 1983).