Print Report

CEGL000180 Pinus ponderosa / Artemisia tridentata ssp. vaseyana / Poa nervosa Woodland

Type Concept Sentence: No Data Available


Common (Translated Scientific) Name: Ponderosa Pine / Mountain Big Sagebrush / Hooker''s Bluegrass Woodland

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This woodland is reported from the Fremont National Forest in Oregon. Elevation ranges from 1770 to 2135 m (5800-7000 feet). Aspect is south to northwest. Slope is 1-25% and slope position is the lower to upper one-third. The topography is flat to convex and also ridgetops. Soils are ash over basalt, andesite and loess. Pinus ponderosa is the most common tree, but Juniperus occidentalis is often found. Pinus contorta and Abies lowiana occur occasionally. Artemisia tridentata ssp. vaseyana occurs in all stands and Symphoricarpos albus and Ribes cereum are common. Common herbaceous species include Poa nervosa, Lupinus argenteus, Achillea millefolium, Elymus elymoides, Carex pensylvanica, Festuca idahoensis, Fragaria virginiana, and Hieracium albiflorum. Fire is important in these forests to maintain the open nature of the forest, with scattered large Pinus ponderosa trees and limited shrub cover.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: No Data Available

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

Physiognomy and Structure: No Data Available

Floristics: Pinus ponderosa is the most common tree, but Juniperus occidentalis is often found. Pinus contorta and Abies lowiana (= Abies concolor var. lowiana) occur occasionally. Artemisia tridentata ssp. vaseyana occurs in all stands and Symphoricarpos albus and Ribes cereum are common. Common herbaceous species include Poa nervosa, Lupinus argenteus, Achillea millefolium, Elymus elymoides, Carex pensylvanica, Festuca idahoensis, Fragaria virginiana, and Hieracium albiflorum.

Dynamics:  Fire is important in these forests to maintain the open nature of the forest, with scattered large Pinus ponderosa trees and limited shrub cover.

Environmental Description:  This woodland is reported from the Fremont National Forest in Oregon. Elevation ranges from 1770 to 2135 m (5800-7000 feet). Aspect is south to northwest. Slope is 1-25% and slope position is the lower to upper one-third. The topography is flat to convex and also ridgetops. Soils are ash over basalt, andesite and loess.

Geographic Range: This association is restricted to southern Oregon east of the Cascades. It is restricted to relatively high-elevation sites with soils rich in pumice. These abiotic requirements cause this association to once have been a common forest type.

Nations: US

States/Provinces:  OR




Confidence Level: Low

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: = Pinus ponderosa / Artemisia tridentata ssp. vaseyana / Poa nervosa (Hopkins 1979a)

Concept Author(s): J. Titus

Author of Description: J. Titus

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.
  • Hopkins, W. E. 1979a. Plant associations of the Fremont National Forest. Technical Report R6-ECOL-79-004. USDA Forest Service, Pacific Northwest Region, Portland.
  • 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.