About Grindelia hirsutula Hook. & Arn.
Grindelia hirsutula Hook. & Arn. is an erect perennial herb or subshrub. It can reach up to 2.5 m (8 ft) tall, though it is typically much shorter. The plant is usually green, but its stems are often red or purplish-brown, and its leaves may range from somewhat yellowish to reddish. It can produce numerous flower heads arranged in branching clusters at the top of the plant. Each flower head is 2–3 cm (3⁄4–1+1⁄4 in) wide, with hemispheric clusters of greenish phyllaries forming a cup at its base. The phyllaries are claw-shaped and bend away from the flowers. The center of each head is filled with many small yellow disc florets, which are surrounded by numerous golden ray florets. The flower head produces a thick white exudate, which is especially prominent in new heads. Grindelia hirsutula is native to North America, and is widespread across Canada, as well as in the U.S. states of California and Oregon. This species is highly variable, and many local populations have been classified as distinct varieties or even separate species. All of these different taxa intergrade with one another, however.
