Hieracium horridum, known as the prickly hawkweed or shaggy hawkweed, gets its name from the long, dense, shaggy white to brown hairs (trichomes) which cover all of the plant parts of this plant species. The species is native to Oregon, California, and Nevada in the western United States. Hieracium horridum possesses oblong leaves along the stems of this 4 inches (10 cm) to 15 inches (38 cm) tall hairy plant with 11-12 bright yellow flower heads at the top of each flower head, which is 0. 315 inches (8 mm) to 0. 354 inches (9 mm) in diameter. It flowers between late June and August. Hieracium horridum's habitat is in dry rocky places within mountainous coniferous forests in Oregon, California and Nevada at elevations between 5,000 feet (1,524 m) and 12,000 feet (3,658 m).