Hesperevax sparsiflora var. brevifolia
by Doreen Smith
Some little obscure annual grey-green “belly-flowers” can be listed rare plants! Here in Marin, this category includes short-leaved evax, Hesperevax sparsiflora var. brevifolia, CNPS 1B.2. Mostly coastal, this species grows on sandy soils and ocean bluffs on Pt. Reyes and near Dillon Beach. The nominate species H. sparsiflora var. sparsiflora is slightly larger and more common. It is usually found in native serpentine grassland areas and not restricted to the coast.
I bet most of us have not closely examined the flowers of either variety of Hesperevax, as they are so small. It may surprise some, for a start, that it is in the sunflower family, Asteraceae. The male part of the inflorescence of one to four tiny flowers is surrounded by a circular-appearing structure of five bracts. The female florets are below on the stem. Even with a 10x lens, it is hard to make out the details of these structures.
Hesperevax sparsiflora var. brevifolia (short-leaved evax) Hesperevax sparsiflora var. sparsiflora