Revised recognition of a high Sierran Potentilla (Rosaceae) as Potentilla amicarum

  • Barbara Ertter University and Jepson Herbaria, University of California and Snake River Plains Herbarium, Boise State University


Potentilla amicarum Ertter is provided for plants from high elevations (2700–3700 m) in the southern and central Sierra Nevada, and also the White and Sweetwater mountains of California, that have most often been treated as depauperate P. drummondii or P. bruceae, or else P. breweri with subpinnate leaves. The name P. breweri var. viridis Jepson has sometimes been applied to these plants, but the type of that name is inter-preted as the hybrid of P. wheeleri and P. breweri. A hybrid origin is hypothesized involving P. breweri, P. drummondii, and/or P. glaucophylla. The size range and elevation of P. bruceae in recent floristic treatments is adjusted accordingly, and the distribution of P. drummondii in California is discussed.


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How to Cite
Ertter, B. (2017). Revised recognition of a high Sierran Potentilla (Rosaceae) as Potentilla amicarum. Journal of the Botanical Research Institute of Texas, 11(1), 11-18.