Description

This little sunflower is encountered almost exclusively on Mt Diablo, at the very northern tip of the Diablo Range in Contra Costa County. As an aside, Mt. Diablo is home to many unique plant species and is always worth a visit. Another two examples of Mt Diablo endemics are the Mt Diablo manzanita, Arctostaphylos auriculata, and the Mt. Diablo fairy lantern, Calochortus pulchellus. Our helianthella grows in sunny, open areas as a component of grassland plant communities. After summer dormancy, which the plant enters regardless of available water, the thick tuber sends up a whorl of lance-shaped leaves. As the plant matures, the clump grows larger with more leaves from each plant and from offsets. Once the Mt. Diablo helianthella has stored adequate energy it sends up one to several stems each topped with a single sunflower. Abundant black seeds are produced as the flowers fade in the summer. Plant Mt. Diablo helianthella in the foreground of other dry-loving natives, perhaps with other geophytes such as yellow mariposa lily, Calochortus luteus, and yampah, Perideridia kelloggii.