Common (Translated Scientific) Name: Threetip Sagebrush / Rough Fescue Shrub Grassland

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This type is a minor component of landscapes generally dominated by Artemisia tridentata ssp. vaseyana in both eastern Washington and western Montana. These are generally arid sites with annual precipitation of 20-60 cm; in Washington elevation ranges between 335 and 915 m (1100-3000 feet), whereas its highly circumscribed Montana distribution ranges between 1280 and 1400 m (4200-4600 feet). In Washington this type is found on northerly aspects where loess soils cap basalt and granite. In Montana this type is found in glaciated landscapes where glacial till derived from metamorphic Belt Series rock predominates, and it occurs on gentle slopes of all aspects. It is possibly more abundant in British Columbia and Alberta. Artemisia tripartita, characteristically less than 60 cm (2 feet) tall, dominates the shrub layer, typically ranging in canopy cover from 10-40%. In Washington, Artemisia tridentata and Purshia tridentata, and in Montana Rosa woodsii, are the shrubs regularly present. On most sites, especially those only lightly grazed, Festuca campestris is by far the dominant herb (canopy cover ranging from 10-60%), but on the most mesic sites its cover can be approached by that of Achnatherum richardsonii and/or Achnatherum occidentale. On more intensively grazed sites Festuca idahoensis cover (or that of other graminoids) approaches or exceeds that of Festuca campestris. Forb diversity is moderate to high; in Montana, Potentilla gracilis, Geranium viscosissimum, Lupinus sericeus, Eriogonum umbellatum and Antennaria microphylla dominate this layer. Washington occurrences contrast with those of Montana by having a well-developed soil crust of mosses, lichens and algae.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: Artemisia tripartita is well known to stump-sprout following fire, and it could be hypothesized that its current dominance in the landscape is associated with past fire regimes. The foregoing hypothesis is made in light of the observation that the distribution of this association (CEGL001537), at least in Montana, does not seem to differ in terms of any readily perceptible environmental variables or landscape positions from ~Artemisia tridentata ssp. vaseyana / Festuca campestris Shrub Grassland (CEGL001531)$$, ~Artemisia tridentata / Festuca idahoensis Shrub Grassland (CEGL001530)$$, or even Festuca campestris - Festuca idahoensis associations. Artemisia tripartita / Festuca campestris differs from Festuca campestris - Festuca idahoensis only in that the former has at least 10% canopy cover of Artemisia tripartita.

Similar NVC Types: No Data Available

note: No Data Available