Plant of the Month ~~ DECEMBER 2006
Most every person who hikes, rides, climbs or works in the Santa Monica Mountains has at one time or another had the unfortunate experience of the rash caused by brushing against this common plant. Most of the literature indicates that the more exposure to the oil (urushiol) from Poison Oak, the more likely we are to experience this rash. In many cases the more times you have the rash the quicker it appears after initial exposure and the more disruptive it is to your life. Unfortunately, the reaction in 10% to 20% of people can be life threatening in as little as four hours of initial exposure. If you are leading a group of fellow adventurers into the local mountains, alerting your group to this danger becomes as important as your message regarding rattlesnakes and mountain lions.
Poison oak is a deciduous shrub that is quite common throughout the mountains and valleys of California. As a rule Poison Oak is not found above 5,000 feet of elevation. In shady canyons and riparian habitats it commonly grows as a climbing vine with roots that cling to the trunks of oaks and sycamores. A National Park Employee told me that it is not uncommon for these vines to stretch from a source of water quite far up the side of a mountain! Poison oak also forms dense thickets in chaparral and coastal sage scrub, particularly in central and northern California. It regenerates readily after disturbances such as fire and trail maintenance. If you are hiking in the Santa Monica Mountains you are going to encounter this plant one way or another! The old adage "Leaves of Three, let it be" has been shortened from its original form. Most of us omit "berries white, a poisonous sight". Poison Oak has male and female plants and flowers in the late Spring. Interestingly, in the early part of Spring the leaves appear shiny and waxy.
During late Summer, the leaves turn various shades of red and yellow. The rash from Poison Oak can be caused when there are leaves on the plant and more importantly when there are no leaves because the urushiol resin is found in the stems and roots of the plant.
What makes exposure to this plant so painful?
How do I make this rash go away!
How do I keep from getting Poison Oak?
My routine is to undress in the garage, place clothes into empty washing machine, notify the wife that I have been traipsing through some Poison Oak. Take a cold shower to rinse the dirt and Urushiol off of my skin. Wash each limb with Tecnu, wait two minutes and rinse off Tecnu. Look at calendar and begin hoping that I removed every single trace of the oil from my gear and me! Other adventurers bring rubbing alcohol packets with them and use them should contact with Poison Oak be made. Don't let this common plant keep you from enjoying the great outdoors!
Should you want to know more?
Contributed by Liz Baumann Contributed by George Sherman
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References:Wildflowers of the Santa Monica Mountains, by Milt McAuley
Flowering Plants: The Santa Monica Mountains, Coastal and Chaparral Regions of Southern California, by Nancy Dale
Roadside Plants of Southern California, by Thomas J. Belzer
California Native Plants for the Garden, by Carol Bornstein, David Fross, and Bart O'Brien
California Herbal Remedies, by LoLo Westrich