Print Report

CEGL000193 Pinus ponderosa / Purshia tridentata / Carex inops ssp. inops Forest

Type Concept Sentence: No Data Available


Common (Translated Scientific) Name: Ponderosa Pine / Antelope Bitterbrush / Long-stolon Sedge Forest

Colloquial Name: No Data Available

Hierarchy Level:  Association

Type Concept: This forest is endemic to the eastern Cascades of central Oregon. It is found on a narrow elevational belt between 1500-1800 m (4900-5900 feet) on level slopes (1-10%) of all aspects. Soils are loamy coarse sand to sandy loams which are well-drained. It is possible that it occurs in deep, recent pumice outcrops in northern California, but it has not been documented there. Pinus ponderosa and Pinus contorta partially shade an understory of Purshia tridentata, Achnatherum occidentale ssp. occidentale, and the diagnostic species Carex inops ssp. inops. Other plants which may be present include Arctostaphylos patula, Ceanothus velutinus, Carex rossii, Elymus elymoides ssp. elymoides, Achillea millefolium, Eriogonum umbellatum, and Machaeranthera canescens. This association is well-adapted to periodic fires.

Diagnostic Characteristics: No Data Available

Rationale for Nominal Species or Physiognomic Features: No Data Available

Classification Comments: All three nominal species are the clear dominants in their respective layers. However, recent fire may decrease Purshia tridentata and favor Ceanothus velutinus or Arctostaphylos patula. This community is similar to the more extensive ~Pinus ponderosa / Purshia tridentata / Carex rossii Woodland (CEGL000194)$$ which does not support Carex inops ssp. inops.

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

Physiognomy and Structure: No Data Available

Floristics: Pinus ponderosa (10-40% cover) and Pinus contorta (1-20% cover) partially shade an understory of Purshia tridentata (7-40% cover), Achnatherum occidentale ssp. occidentale (= Stipa occidentalis) (trace-10% cover), and the diagnostic species Carex inops ssp. inops. Other plants which may be present include Arctostaphylos patula, Ceanothus velutinus, Carex rossii, Elymus elymoides ssp. elymoides (= Sitanion hystrix), Achillea millefolium, Eriogonum umbellatum, and Machaeranthera canescens (= Aster canescens).

Dynamics:  This association is well-adapted to periodic fires.

Environmental Description:  This forest is endemic to the eastern Cascades of central Oregon. It is found on a narrow elevational belt between 1500-1800 m (4900-5900 feet) on level slopes (1-10%) of all aspects. Soils are loamy coarse sand to sandy loams which are well-drained. It is possible that it occurs in deep, recent pumice outcrops in northern California, but it has not been documented there.

Geographic Range: This is endemic to the eastern Cascades of Oregon. It is possible that it occurs in deep, recent pumice outcrops in northern California, but it has not been documented there.

Nations: US

States/Provinces:  CA?, OR




Confidence Level: Low - Poorly Documented

Confidence Level Comments: No Data Available

Grank: G2

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 / Purshia tridentata / Carex inops ssp. inops Forest (DiPaolo et al. 2018)
= Ponderosa Pine / Bitterbrush / Sedge (Volland 1985)

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.
  • DiPaolo, D. A., D. C. Odion, K. M. Rolih, P. Adamus, and D. A. Sarr. 2018. Vegetation classification and mapping: Crater Lake National Park. Natural Resource Report NPS/CRLA/NRR--2018/1663. National Park Service, Fort Collins, CO. 550 pp.
  • 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.
  • Volland, L. A. 1976. Plant communities of the central Oregon pumice zone. USDA Forest Service R-6 Area Guide 4-2. Pacific Northwest Region, Portland, OR. 113 pp.
  • Volland, L. A. 1985. Plant associations of the central Oregon pumice zone. USDA Forest Service R6-ECOL-104-1985. Pacific Northwest Region, Portland, OR. 138 pp.
  • Western Ecology Working Group of NatureServe. No date. International Ecological Classification Standard: International Vegetation Classification. Terrestrial Vegetation. NatureServe, Boulder, CO.