Metadata Download  View Map Services More Info
Species Information
Observations Animal 
Request Snapshot
Field Guide
SOC Species Occurrences Animal 
Request Snapshot
- -
Animal Structured Surveys Request MapViewer - -
Range Maps -- Animals - Request MapViewer
Field Guide
- -
Predicted Suitable Habitat - Predicted Models - -
Ecological Information
Land Cover MapViewer -
Wetlands and Riparian Mapping MapViewer
Land Management Information
Public Lands MapViewer -
Conservation Easements MapViewer -
Private Conservation Lands MapViewer -
Managed Areas MapViewer -
Weyerhaeuser Lands MapViewer -
Montana Geographic Information
Montana Geographic Information - -

Community Field Guide

Scientific Name:
Artemisia tripartita / Pseudoroegneria spicata Shrub Herbaceous Vegetation

Common Name:
Threetip sagebrush / bluebunch wheatgrass Shrub Herbaceous Vegetation

Community Description

This plant association is reported from sites located in the Okanogan Highlands, Columbia Basin, Snake River Basalts, Northwest Basin and Range, Beaverhead Mountains, and Overthrust Mountains ecoregional sections. Artemisia tripartita is the dominant shrub in the relatively open stands. With good ecological conditions, Pseudoroegneria spicata is abundant in the understory. Koeleria macrantha and Poa secunda are usually present but not abundant. The association is reported to support a rich assembly of herbaceous species, but none of the authors provides much detail on this component of the species composition. Soil moss and lichen cover can be as high as 80%.

Artemisia tripartita / Pseudoroegneria spicata is a community of very limited acreage in the Beaverhead Mountains Section, noted only south of the Clark Fork Reservoir. It almost always occurs as small or linear patches on west- to south-facing ridges and convex slope shoulder sites where solar insulation and prevailing winds exceed the tolerance of Festuca idahoensis. These sites usually have an abrupt transition to Artemisia tripartita / Festuca idahoensis or Artemisia tridentata ssp. vaseyana / Festuca idahoensis of less moisture- Stressed positions.

These droughty sites have insufficient cover (10%-20%) of Artemisia tripartita to be considered shrub stands. Other shrubs that occur, generally with less than 5% cover, include Chrysothamnus viscidiflorus, Artemisia frigida and Artemisia tridentata ssp. vaseyana. Pseudoroegneria spicata and Koeleria macrantha (=Koeleria cristata) dominates the herbaceous layer, though their coverage is commonly less than 30%. Forbs often include Phlox hoodii, Achillea millifolium, Antennaria parviflora, Arabis microphylla and Erigeron compositus, none having more than 5% cover.

Global Rank: G2G3 State Rank: S?

Global Rank Comments:
This is a somewhat widespread plant association occurring with relatively few, small stands in a sporadic, discontinuous distribution. It occurs in the Okanogan Highlands, Columbia Basin, Snake River Basalts, Northwest Basin and Range, Beaverhead Mountains, and Overthrust Mountains ecoregional sections. The physical environmental parameters of this vegetation type are not well defined. Many stands are easily accessed and grazed by livestock. Approximately 50 percent of the occurrences are considered to be in poor condition.

Community References


99-11-16 / S. V. Cooper, MTNHP

Bourgeron and Engelking 1994, Caicco and Wellner 1983i, Caicco and Wellner 1983j, Daubenmire 1970, Driscoll et al. 1984, Hironaka et al. 1983, McLean 1970

View Detailed Citation Information | New Community Search | NatureServe Explorer Community Information

This information is from the:
Montana Natural Heritage Program
Montana State Library--Natural Resource Information System
1515 East Sixth Ave., Helena, MT 59620-1800
406 444-5354