About Holocarpha virgata (A.Gray) D.D.Keck
Holocarpha virgata is an annual herb that grows an erect stem between 20 centimeters (7.9 inches) and over 1 meter (3.3 feet) tall. It produces many branches, and its entire structure is covered in oily glands and hairs. The plant has linear leaves: those near the base reach up to 15 centimeters (5.9 inches) long, while leaves growing along the stem are much smaller. Its inflorescence consists of multiple short branches densely lined with small, thick green bracts. These bracts are only a few millimeters long, and each is tipped with a gland. Flower heads grow at the ends of the branches, and each head is surrounded by phyllaries covered in knobby resin glands. Each flower head holds 9 to 25 yellow disc florets with black or purplish anthers, and a fringe of 3 to 7 yellow ray florets that often have lobed tips. There are two recognized subspecies: Holocarpha virgata subsp. elongata D. D. Keck, found in San Diego County, western Riverside County, and Orange County; and Holocarpha virgata subsp. virgata, found in the Central Valley and surrounding areas. This species is endemic to California. It is most common in the San Joaquin Valley and Sacramento Valley that make up the Central Valley, as well as the adjacent foothills of the Inner Coast Ranges and the U.S. Sierra Nevada. Additional populations occur in the foothills of the Peninsular Ranges in San Diego County, western Riverside County, and Orange County.
