Outdoor Safety for Families Part 1: Poison Oak is Not Your Friend

Summer is here, and it's time for families to enjoy popular outdoor activities like hiking and camping. Since kids don't always pay attention to their surroundings and potential hazards, it's up to us as parents and caregivers to watch out for them. The goal of our series of outdoor safety posts is to give parents and caregivers an introduction to some of the common safety hazards found in Northern California, with an eye toward children's safety in particular. Of course, none of this should be a substitute for genuine medical advice.

Western or Pacific Poison-oak (Toxicodendron diversilobum), is found all along the west coast, from Baja to southern Canada, and is one of the most common plants seen around trails and campsites in California. It's also one that just about everyone really wants to avoid. Anyone who's ever had poison oak will tell you that the old axiom "Leaves of three, let them be" is something to live by. Most of the year, this plant has distinctive, shiny leaves grouped in threes. Bright green in the spring, they turn reddish in the summer, and by fall they're a bright and not unattractive red or pink. This plant can be found in shrub form, often in large amounts, or in vine form climbing up and around trees. It's not actually related to the oak tree (which is why it's officially spelled "poison-oak," not "poison oak"), although the leaves look a little similar, but it's often seen on and around oak trees.

The "poison" in poison-oak is a noxious substance called urushiol. The first symptom of contact with poison-oak is a severe itch, accompanied by either a red rash, colorless bumps, or both. This irritation later breaks out into blisters. Scrathing the blisters can cause them to ooze fluid, which, contrary to urban legend, does not spread the poison oak on the victim's skin or to other people. The urushiol bonds quickly to the skin, and once it does, you're pretty much guaranteed to develop the rash, unless you're one of the lucky few who is not affected by poison oak (it's estimated that 15–30% of the population is not allergic to poison oak, but a sensitivity can build up over time, so it's best to avoid it no matter what). If you know you had contact with poison oak, you can alleviate some of the effects by washing the affected area immediately with cool water, but this is not a guarantee that you won't get it.

The oils from poison-oak can last for a long time, and you can pick up a nasty case of poison oak by touching something else that was exposed, such as clothing, tools, and of course the family pet (ever wonder where your cat goes during the day). Personally, I've picked up cases of poison oak when I was certain that I hadn't been anywhere near it, and the likeliest source was the family cat who had been out wandering (or more likely sleeping) in the woods during the day. I've heard rumors, or possibly urban legends, that extreme heat can cause poison-oak oils to become airborne, so cases of poison oak can be picked up just by being in close proximity to the plant. Again, I'm not sure this is true, but I'm in no hurry to test the theory.

If you think you or your children have been exposed to poison oak, it's best to bathe or shower as soon as possible in lukewarm water, and wash all clothing immediately. If anyone develops a case of poison oak, its best to contact your family doctor or a dermatologist.

Poison oak is annoying, irritating, and uncomfortable, but generally not life threatening. It's even worse when ingested, or inhaled in the form of smoke. Apparently most of the firefighters helping contain the blaze down in Big Sur are coming down with pretty awful cases, but then it's an occupational hazard when you're tramping through the woods all day.

Here are some links to poison oak info online:

• Poison-oak information from the American Academy of Dermatology
• Western Poison Oak photo gallery