Purshia tridentata

Purshia tridentata is a member of the rose family (Rosaceae), named in honour of the botanist Frederick T. Pursh (1774-1820). The species is similar to and hybridizes with Desert Bitterbrush (Purshia glandulosa) and Stansbury Cliffrose (Purshia stansburiana). It is similar with three-parted leaves, as well as often growing in association with Big Sagebrush (Artemisia tridentata) however lacks the characteristic 'sage' odour of Big Sagebrush. FNA (vol. 9, 2014) includes P. glandulosa (= P. tridentata var. glandulosa) as a variety of P. tridentata. Therefore according to FNA, Kartesz`s (1994) P. tridentata is equivalent to P. tridentata var. tridentata.

Purshia tridentata is a widespread native and endemic species which has a broad ecological amplitude. Some populations are showing decline and lack of regeneration after fire events, as well as overgrazing. Although this is a fire-, browse- and drought-adapted species, the plant's response to these impacts depends on the time of year, the intensity, the age of the plant, specific microclimate at its location, as well as recovery time (in years) the plant may need without another impact event

Antelope bitterbrush (Purshia tridentata) is a wide-ranging native shrub in western North America. It occurs from southern British Columbia, Canada; through to Washington and Oregon east of the Coast-Cascade Mountains; southeast into Idaho and western Montana; towards the coast in the Klamath, North Coast, Cascade, Sierra Nevada, Tehachapi, Transverse, Peninsular ranges and Great Basin/Desert Mountains floristic provinces of California; throughout the Rocky Mountains; in the Great Plains Basin; and into Arizona and New Mexico of the United States.

Purshia tridentata is affected by habitat loss/degradation, natural ecological processes such as drought and fire, exotic species and overgrazing by livestock or other herbivores. In addition, many antelope bitterbrush ecosystems are at risk from development, including the demand for vineyards for the wine industry. As an arid-land adapted species, the geographic range of P. tridentata may expand with the anticipated climate change scenario involving warmer temperatures and reduced precipitation in the western region of the U.S. In Canada, the shrub occurs only in southern British Columbia and its habitat occupying only 0.2% of a small area of B.C. is considered one of Canada's four most endangered ecosystems (Schluter et al. 1995).