Technical Report

Vegetation of vernal pools and related ephemeral wetlands in the Gerber Block, Klamath Basin, Oregon, including searches for Orcuttia tenuis and Tuctoria greenei

Public Deposited

Downloadable Content

Download PDF


Attribute NameValues
  • The California vernal pool-endemic grasses Orcuttia tenuis and Tuctoria greenei, both listed under the U.S. Endangered Species Act, were recently found in Modoc County, California, a short distance south of the Oregon border. This prompted searches in suitable habitats in adjacent portions of the Klamath Basin in Oregon, in the Gerber Block Bureau of Land Management lands and adjacent portions of the Fremont- Winema National Forest. Neither species was found in the 2010 or 2011 surveys. The 2009-2010 winter through summer was very dry, possibly causing dormancy of these species in soil seed banks that year. The 2010-2011 winter through summer was much wetter, so much so that the pools desiccated very late, perhaps furthering dormancy. Alternately, the species may truly be lacking from the Gerber Block. Twenty-six species ranked for conservation by the Oregon Biodiversity Information Center were found in the 2010 surveys, and an additional 10 species were found that should be considered for listing as conservation priorities in Oregon. A number of vascular plants and lichens were found that may represent taxa new to science. In vernal pools, 149 taxa (all but 9 of them native) were recorded. A preliminary sketch is given of character species, high-frequency species, species autecologies, and plant communities of vernal pools in the project area. Further notes describe additional ephemeral wetland types encountered in the project area.
  • KEYWORDS: Fremont Winema National Forest, Endemic grasses, Wetland plants, Vernal pools, Modoc County, California, Klamath County, Oregon, Gerber Block Bureau of Land Management, Klamath Basin
Resource Type
Date Available
Date Issued
  • Björk, Curtis R. Vegetation of Vernal Pools and Related Ephemeral Wetlands in the Gerber Block, Klamath Basin,Oregon, including searches for Orcuttia tenuis and Tuctoria greenei. Report to USDI Bureau of Land Management, Lakeview District, Klamath Falls Office and the Oregon Biodiversity Information Center, Portland State University. Stillinger Herbarium, University of Idaho, Moscow, Idaho. September 2011.
Non-Academic Affiliation
Rights Statement
Funding Statement (additional comments about funding)
  • USDI Bureau of Land Management
  • Klamath Falls Office
  • Lakeview District
  • Oregon Biodiversity Information Center, Portland State University



This work has no parents.

In Collection: