Coyote Brush of California's Coastal Scrub and Chaparral

In addition to being a birder's dream come true, California and its wide range of floristic provinces is a treat for botanists as well.  Coyote Brush (Baccharis pilularis), an evergreen shrub in the sunflower family (Asteraceae), is characteristic of several of California's unique plant communities, from coastal scrub to foothill chaparral. 

 

Coyote Brush provides valuable wildlife habitat at San Luis National Wildlife Refuge, Merced County

 

Coyote Brush is characteristic of the Northern Coastal Scrub and Coastal Sage Scrub plant communities and closely associated with adjacent closed-cone pine forests.  It is also a characteristic component of foothill chaparral.  The coastal scrub communities are referred to as "soft chaparral," since the leaves are literally softer than those of the true "hard chaparral" and landscapes of soft chaparral have an overall softer appearance.

 

Northern Coastal Scrub is found directly inland from the beaches, dunes and coastal bluffs of Northern California.  It differs from the Coastal Prairie (which consists primarily of grasses and is now largely destroyed) and the Coastal Strand (comprised of low-growing plants like sand verbena and beach evening primrose) in that Northern Coastal Scrub contains a high number of shrubs.  And one of these is Coyote Brush. 

 

Northern Coastal Scrub, predominately consisting of Coyote Brush, near Stinson Beach, Marin County.

 

South of Big Sur, Northern Coastal Scrub transitions to its southern counterpart, Coastal Sage Scrub, which is found along the coast into Baja California.  Here sages (Salvia spp.) are present which are absent in the north.  The soft chaparral community of the coast provides breeding habitat for Allen's Hummingbirds (Selasphorus sasin) and Nuttall's White-crowned Sparrows (Zonotrichia leucophrys nuttalli).  A great number of bird species are associated with Coyote Brush along the coast.  Most commonly, these include: Wrentit, Bewick's Wren, American Goldfinch, California Quail, Nuttall's White-crowned Sparrow, California and Spotted Towhees, California Thrasher.

 

Bewick's Wren in the leaf litter beneath Coyote Brush, San Joaquin River NWR, Stanislaus County

 

Coyote Brush grows close to the ground where it is effectively "pruned" by wind, as on the coast.  In protected sites and farther inland, it can grow over 6 feet tall.  The small leaves of Coyote Brush are covered in a waxy coating to aid in the plant's ability to withstand drought and deter herbivores.  This shrub is also well-adapted to fire, readily re-sprouting after a blaze.

 

Coyote Brush as part of Northern Coastal Scrub at Salinas River NWR, Monterey County

 

Coyote Brush is dioecious, which means that male and female flowers are produced on separate plants; each plant is either male or female. 

 

Backing up a little to Botany 101, we must remember that not all plants produce "perfect" flowers, with male and female parts occuring on the same flower - for example, the stamen (male) and pistil (female) that occur on each rose flower.  Plants that produce "imperfect" flowers - flowers lacking one of the reproductive parts - are either dioecious, with separate male and female plants, or monoecious, with separate male and female flowers occurring together on one plant. 

Male flowers on a strictly male Coyote Brush

A few other dioecious plants you may be familiar with are hollies; in order to get those lovely red berries, you have to plant a female holly bush, with a male nearby.  Ginkgo trees are also dioecious, but you'd better plant only male ginkgos, or you will find yourself with a mess of extremely stinky fruit every year! 

Oaks are familiar examples of monoecious plants, with conspicuous male catkins and inconspicuous female flowers.  Squash plants also produce separate male and female flowers, which is why it's okay to pick the male squash flowers for garnish and not worry that half of the plant's flowers didn't produce fruit - a valuable lesson from my years as an organic market farmer!

 

There is your impromptu botany lesson for the day!

Coyote Brush blooms in the fall, from about August through December.  It is pollinated by native bees, parasitic wasps and small butterflies.  The fruit is very small, borne on a fluffy tuft of white "hairs," reminiscent of a miniature dandelion.  Like dandelions (also members of Asteraceae), Coyote Brush seeds are dispersed by the wind.
 

Female Coyote Brush flowers, dispersing their fluffy seeds.

Though Coyote Brush is typically associated with chaparral and scrub plant communities on the coast and in the foothills, it can also be found in the Great Central Valley.  It has been planted extensively along the levee roads at the San Joaquin River National Wildlife Refuge, along with California Wild Rose (Rosa californica) and Blue Elderberry (Sambucus nigra), to provide cover for endangered Riparian Brush Rabbits when the low-lying parts of the refuge are flooded (which is a natural part of the restoration of the river's flood plain).  Since 1999, River Partners and the San Joaquin River NWR have been working toward the goal of restoring habitat for endangered Riparian Brush Rabbit and Valley Elderberry Longhorn Beetle, as well as conserving habitat for riparian bird species, like the Yellow Warbler and endangered Least Bell's Vireo.  Coyote Brush has been a valuable part of restoration efforts, and today, California Thrashers, formerly driven out of the valley by habitat loss, can be seen and heard singing from the tops of Coyote Brush.
 

Coyote Brush along the levees at San Joaquin River NWR, Stanislaus County, provides valuable wildlife habitat.

In addition to restoration plantings, Coyote Brush also works well in native plant landscapes at home, particularly the low-growing ground cover form, 'Pigeon Point.'  Most landscape cultivars are male, to avoid fluffy seeds blowing all over the yard.  Sometimes called Chaparral Broom, Coyote Brush is not to be confused with the non-native and highly invasive yellow-flowered Scotch Broom that is used in the landscape industry and has escaped captivity much to the detriment of California's coastal scrub and chaparral communities!