Print Report

CEGL000194 Pinus ponderosa / Purshia tridentata / Carex rossii Woodland

Type Concept Sentence: No Data Available


Common (Translated Scientific) Name: Ponderosa Pine / Antelope Bitterbrush / Ross'' Sedge Woodland

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This woodland is found in the southern Blue Mountains, the Ochoco Range, and southeastern Oregon Cascades. Elevations are between 1020-1980 m (3350-6500 feet) with generally low steepness (0-50%) and a variety of aspects, but favoring southerly exposures in the Blue Mountains. Soils are sandy loams, silt, and loamy sand. The overstory is dominated by Pinus ponderosa with occasional Juniperus occidentalis. The shrub layer is characterized by Purshia tridentata and occasional Mahonia repens. The herbaceous layer is usually dominated by Carex rossii. Other herbaceous species include Achnatherum occidentale ssp. occidentale and Elymus elymoides ssp. elymoides. Occasionally, Achillea millefolium and Fragaria virginiana are present. This association is well-adapted to periodic surface fires which promote regeneration of Pinus ponderosa. It occupies warm and moist sites as compared to other Pinus ponderosa / Purshia tridentata associations.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: In Washington, this association is considered part of ~Pinus ponderosa / Purshia tridentata Central Rocky Mountain Woodland (CEGL005648)$$. Fairly good confidence for the classification. At least three different sources/analysts have described this community using the same name.

Similar NVC Types: No Data Available
note: No Data Available

Physiognomy and Structure: No Data Available

Floristics: The overstory is dominated by Pinus ponderosa (25-53% cover) with occasional Juniperus occidentalis (0-4% cover). The shrub layer is characterized by Purshia tridentata (5-37% cover) and occasional Mahonia repens (0-36% cover). The herbaceous layer is usually dominated by Carex rossii with 10-46% cover. Other herbaceous species include Achnatherum occidentale ssp. occidentale (= Stipa occidentalis) (3-10% cover) and Elymus elymoides ssp. elymoides (= Sitanion hystrix) (5-10% cover). Occasionally, Achillea millefolium and Fragaria virginiana are present.

Dynamics:  This association is well-adapted to periodic surface fires which promote regeneration of Pinus ponderosa. It occupies warm and moist sites as compared to other Pinus ponderosa / Purshia tridentata associations.

Environmental Description:  This woodland is found in the southern Blue Mountains, the Ochoco Range, and southeastern Oregon Cascades. Elevations are between 1020-1980 m (3350-6500 feet) with generally low steepness (0-50%) and a variety of aspects, but favoring southerly exposures in the Blue Mountains. Soils are sandy loams, silt, and loamy sand.

Geographic Range: This association is only documented from Oregon''s eastern mountains. It might be found in northern California or western Idaho, but has not been reported from either state.

Nations: US

States/Provinces:  OR




Confidence Level: Low - Poorly Documented

Confidence Level Comments: No Data Available

Grank: G2G3

Greasons: No Data Available


Concept Lineage: No Data Available

Predecessors: No Data Available

Obsolete Names: No Data Available

Obsolete Parents: No Data Available

Synonomy: No Data Available

Concept Author(s): M.P. Murray

Author of Description: M.P. Murray

Acknowledgements: No Data Available

Version Date: 11-26-97

  • Bourgeron, P. S., and L. D. Engelking, editors. 1994. A preliminary vegetation classification of the western United States. Unpublished report. The Nature Conservancy, Western Heritage Task Force, Boulder, CO. 175 pp. plus appendix.
  • Dealy, J. E. 1971. Habitat characteristics of the Silver Lake mule deer range. Research Paper PNW-125. USDA Forest Service, Pacific Northwest Forest and Range Experiment Station, Portland, OR. 99 pp.
  • Hall, F. C. 1973. Plant communities of the Blue Mountains in eastern Oregon and southeastern Washington. R6 Area Guide 3-1. USDA Forest Service, Pacific Northwest Region, Portland, OR. 62 pp.
  • Johnson, C. G., and R. R. Clausnitzer. 1992. Plant associations of the Blue and Ochoco mountains. R6-ERW-TP-036-92. USDA Forest Service, Pacific Northwest Region, Wallowa-Whitman National Forest. 163 pp. plus appendices.
  • Kagan, J. S., J. A. Christy, M. P. Murray, and J. A. Titus. 2004. Classification of native vegetation of Oregon. January 2004. Oregon Natural Heritage Information Center, Portland. 52 pp.
  • Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.