Each year, depending on the rainfall, temperature and ?, a different set of plants seems to predominate along roadsides and fence rows, and in pastures, fields and waste areas. This year in northeastern California, the common sunflower is one of the prevalent species.
Helianthus annuus is native to North America and has been cultivated since pre-Columbian times. This is the species most people associate with “sunflower”. Cultivated varieties of H. annuus are often much larger than wild plants and have flowers, seed heads and seeds that are huge by comparison. The edible seeds of this annual were eaten by indigenous peoples or pressed into a nutritious oil.
Also called hairy-leaved sunflower or wild sunflower, the common sunflower has an erect, much-branched stem covered with stiff hairs. The oval or heart-shaped leaves have toothed edges and alternate on the stem. The familiar flower head is formed from yellow ray flowers surrounding a central cluster of brown or red-brown disc flowers. Although the seeds in cultivated varieties are large and plump, the seeds (achenes) of wild sunflower plants are only a quarter of an inch long, wedge-shaped and flattened. I occasionally will nibble on a few wild sunflower seeds while walking in our fields or pastures, but there is not much reward for the effort required to shell the seeds.
Common sunflower is an aggressive, invasive plant. Along roadsides or fence rows it is a pretty wildflower. However, when sunflowers invade fields, pastures or agricultural crops they become noxious weeds. As an annual, the plants die each year. Particularly in our arid environment, the stems and seed heads will persist for several years as brittle, gray ghosts – beautiful in their own stark way, but not nearly as cheerful as the sunny yellow flower heads.
The scientific genus name, Helianthus, derives from “helio” meaning “sun” and the word for flower, anthus. Annuus, the species, refers to the fact that common sunflowers are annuals.
The common sunflower is the Kansas state flower.
These wild sunflowers are growing along a fence row on our property (Modoc County CA).