Every second Saturday of the month, CWC (Coastal Watershed Council) leads River Health Days where volunteers help plant and care for a variety of native plant species to increase biodiversity and habitat complexity and support a healthy river ecosystem. Deerweed (Acmispon glaber) is one beneficial plant you may spot growing along the river.
Deerweed is a perennial subshrub that is found in a variety of different types of habitats mainly: chaparral, coastal sand, roadsides and other disturbed areas. It’s a pioneer species to areas of California, Arizona, and Mexico. Blooming from early spring to late summer, they blossom in clusters along the stem with bright yellow inflorescences that turn reddish with age. The flowers then bear one or two seeds. They can grow 1-3 ft tall and 2-3 ft wide.
Deerweed is a highly valued native plant for its flowers and the pollinators that it attracts. With a variety of insects such as host plant to Bramble Hairstreak, Afranius Duskywing, Persius Duskywing, and Acmon Blue butterflies. It is a nectar plant for other butterflies including the Chalcedon Checkerwing. Not only do butterflies benefit from Deerweed but a host of other insects and animals as well. Their seeds help feed birds and rodents. As well as act as forage for deer usually after fires or drought years. In addition, its nitrogen-fixing abilities help with habitat restoration projects.
Deerweed has been known to be used by the Ohlone as a fibrous foliage for building material especially in house thatching. Deerweed has also been used as a decoction for coughs. While it’s said that the Chumash would use the smoke from Deerweed to blacken Juncus to be woven into baskets.
The Palos Verdes blue is a small endangered butterfly which often lays their eggs on Deerweed. As such they are a very important species in assisting with the repopulation of the Palos Verdes blue butterflies.
Love Deerweed? Join CWC for a River Health Day!
You can make a difference in the San Lorenzo ecosystem by caring for Deerweed and other native plants that enhance the ecological value of San Lorenzo River habitat. Join other volunteers at monthly River Health Days to plant more native species. Sign up below!