» "Cowania" redirects here. The gossamer-winged butterfly genus's now 'Ahmetia. Purshia (bitterbrush or cliff-rose)'s a small genus of 5-8 species of flowering plants in the family Rosaceae, native to western North America, where they grow in dry climates from southeast British Columbia in Canada south throughout the western United States to northern Mexico. They're deciduous or evergreen shrubs, typically reaching 0.3-5 m tall. The leaves are small, 1-3 cm long, deeply three- to five-lobed, wi… (More on Purshia)