In the mountains of the eastern Mojave Desert in California, Encelia virginensis may intergrade with E. actoni at higher elevations, probably as a result of hybridization. Plants of E. virginensis in New Mexico may be adventive.
FNA 2006, Benson and Darrow 1981
Common Name: Virgin River brittlebush Duration: Perennial Nativity: Native Lifeform: Shrub General: Much branched shrub 50-150 cm tall with slender hairy branches, developing fissured bark, stems with simple spreading hairs, glabrous with age. Leaves: Cauline, on petioles 2-7 mm, ovate to deltate blades, gray-green,12-25 mm, apices acute or obtuse, faces sparsely canescent and strigose. Flowers: Heads borne singly on canescent peduncles, involucres 9-13 mm, narrowly ovate phyllaries; 11-21 ray florets, 8-15 mm, disc corollas yellow 5-6 mm. Fruits: Cypselae 5-8 mm with no pappus to rarely 1-2 bristlelike awns. Ecology: Found on flats, along washes, and on slopes from 1,000-4,000 ft (305-1219 m); flowers April-June. Notes: Leaves folded along mid-vein, ashy with short, fine , appressed hairs and stouter forward directed hairs from tubercules help to separate this plant out; not farinose and the heads are borne singly helps to separate it from E. farinosa, while the color of the leaves separates it from E. frutescens. Usually lower in elevation and petiolate. Ethnobotany: Var. actonii (found in the Mohave desert) was used for rheumatic pains, and as a wash for cuts and bruises on horses. Etymology: Encelia is named for Christoph Entzelt (1517-1583) a German naturalist, while virginensis is named for the Virgin River in southern Utah, its type locality. Synonyms: Encelia frutescens var. virginensis, Encelia virginensis var. virginensis Editor: SBuckley, 2010