Poa mansfieldii (Poaceae), a new species endemic to Steens Mountain, Oregon, U.S.A.


  • Barbara L. Wilson Carex Working Group
  • Nick Otting Botany and Plant Pathology Department, Oregon State University
  • Richard E. Brainerd Stonecrop LLC




A short, rhizomatous, gynodioecious Poa occurs on alpine slopes below melting snowbanks on Steens Mountain, an isolated, fault-block mountain in southeast Oregon. It was included in P. chambersii, a dioecious species of Oregon’s Cascade Range with cobwebby hairs on at least the lower calluses, although the Steens Mountain form is gynodioecious and its calluses are glabrous. These differences between the Cascadian and Steens Mountain forms were recognized (Soreng 1998, 2007). The Steens Mountain bluegrass is here described as a narrowly endemic species, Poa mansfieldii.


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How to Cite

Wilson, B. L., Otting, N., & Brainerd, R. E. (2019). Poa mansfieldii (Poaceae), a new species endemic to Steens Mountain, Oregon, U.S.A. Journal of the Botanical Research Institute of Texas, 13(1), 19–30. https://doi.org/10.17348/jbrit.v13.i1.823