Anacardia (Sumac Family)

The plants of Anacardiaceae (Sumac family) are shrubs and trees that have a milky or resinous sap that is often pungent. The alternating leaves may be simple or compound, and the flowers are small. Species may be either single or mixed sex. The calyx has 5 lobes, and there are usually 5 petals and 10 stamens. This family includes the Mango, Pistachio, and the Cashew, and for those from back east, Poison Ivy and Poison Sumac.

The Bay Area has only two native respresentatives of this family; which are very similar in appearance to each other. The first is Poison Oak, a plant to be avoided because contact can cause a servere dermatitis in most people. The other, called Skunkbush, is not likely to cause any problems, and is an attractive, easily grown shrub for native gardens, especially if you wish to trick the neighbors into thinking you're growing Poison Oak in the yard.

Of the two, only Poison Oak grows on Montara Mountain.



 Toxicodendron diversilobum:
Poison Oak

Anacardiaceae (Sumac Family)

Flowers: Whitish-green, small; in dangling clusters.

Blooms: April - June.

Leaves: Three distinct leaflets per leaf; glossy red-green in spring when young, shiny green and darker in summer, red in autumn.

Fruit/Seeds: Smooth green balls ripening to white; in dangling clusters; simultaneous or shortly following bloom, ripening in Summer.

Location: It's everywhere.

Status: Native - Common.

Toxicodendron diversilobum

Note the small clusters of flowers and berries, as well as the red-to-green coloring of the leaves. 640x480 JPG - 44K

 Further description & Comment: Sprawling. climbing vine or bushy shrub. Deciduous. 1 - 8 ft tall. One the "signature" plants of coastal scrub and chaparral. Usually growing with other signatures (Coastal Sage, Coyote Bush, Yellow Bush Lupine and Sticky Monkey Flower).

Sometimes, it can be confused with California Blackberry (Rubus ursinus), which has similar looking "leaves of three". The Blackberry has spiny stems, prickly leaves, and large, five petal, star-shaped flowers.

Some folks claim that Artemesia douglasiana (Mugwort) can cure the effects of Poison Oak, but I wouldn't count on it.

 In the summer, Poison Oak is a beautiful, lush, shiny green and red bush, easy to identify. Here it grows mixed in with Coastal Sage in McNee Ranch State Park.  In the winter, though, Poison Oak can look like a pile of dead branches. Note the distinctive branching pattern - learning this can save you a lot of grief after winter hikes.
 Watch out for reaching fingers of it protuding across trails. Leaves or no leaves, all parts of the plant are toxic at all times of the year - there is no safe time to handle Poison Oak!


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