Excerpts from Jim Conrad's
Naturalist Newsletter

California Buckthorn, or Coffeeberry, RHAMNUS CALIFORNICA

from the the August 30, 2009 Newsletter, issued from the Siskiyou Mountains west of Grants Pass, Oregon:

At a steep, rocky roadcut at about 4000 feet near Onion Mountain the woody shrub shown above got my attention. One eye-catching feature is that somehow it managed to be so green and healthy looking in such an austere, dry, sun-baked environment. Another feature is shown below:

California Buckthorn, or Coffeeberry, RHAMNUS CALIFORNICA, fruits

Pretty red fruits mingled with pretty black fruits, with no fruit I could find midway black and red.

I've seen leaves and fruits similar to this on small trees back East -- on Carolina Buckthorns, of the genus Rhamnus. And, sure enough, the Onion Mountain tree turns out to be California Buckthorn, or Coffeeberry, RHAMNUS CALIFORNICA. Cultivated sometimes for its evergreen leaves and colorful fruits, the species is native from here in southwestern Oregon to southwestern California.

Coffeeberry's fruits look like coffee beans but you can't make coffee from them. I read that Native Americans ate the fruits, but I find them a bit tasteless with little flesh surrounding the three or so seeds. The bark was used by native folk as a laxative, but it's known that too much of it is poisonous. In many areas the fruits are often the only abundant "juicy" fruit available in the fall and are readily eaten by birds, Black-tailed Deer, and Black Bear.