LEAVES OF THREE…

by Darrin Gunkel

Pacific, or western, poison oak, known in the science world as Toxidendron diversilobum, (“diverse-leaved toxic tree” in rough translation), is almost as much fun as that other hiker’s menace, the tick. While ticks seem to favor the Gorge, a run-in with poison oak can happen just about anywhere your hikes and climbs take you. Like many a “nuisance,” the plant is perhaps misunderstood. To remedy that, here are some gathered facts and advice, much of which you may not need to know, but which may take your mind off the itching for a few minutes.

The cause of the itching and rash is poison oak’s load of urushiol oil. "Almost everyone is allergic to it," says the website clevelandclinic.org. So, you're in good company, or bad company. It's your glass. Just as long as it's not half full or empty with urushiol oil. The site goes on to explain that if you are unlucky enough to find yourself downwind from burning poison oak, “You may develop a rash on your face…or on the lining of your nasal passages, mouth, and throat from inhaling the smoke. Oil in the air also affects your lungs and can cause serious breathing problems.” As usual, consulting the web does not bring peace of mind.

However, urushiol oil is not all evil: For millennia, it has been the source of the shiny lacquer used in Asia to finish fine arts and crafts. The urushiol oil in lacquer comes from Toxidendron vernicifluum, aka the lacquer tree, appropriately. Or unfortunately, if you’re the type of arty hipster who likes brewing and concocting substances at home, it’s not likely you could extract enough of the substance from our local source, even as plentiful as poison oak is.

It’s a beautiful plant: glossy, pleasingly oak-leaf-shaped foliage that, over the course of a growing season can change from bronze to bright green, to red or pink. Poison oak can sprout from seeds or rhizomes, the fibrous bulbs in plant roots. Rhizomes are one of the reasons you may see it in big ground-covering mats, usually ankle- to knee-deep and too wide to jump across safely or step out of easily once you’ve wandered deep into danger. Take heart, the plant is a nitrogen fixer, transferring that nutrient element from the atmosphere to the soil, where poison oak and other plants can make use of it. It’s a(n ecological) team player!

It’s like a travel buddy: poison oak can be found from British Columbia to the Baja. Almost as ubiquitous as fast food or Walmart, but less dangerous to your health or the world’s well-being.

Impress your pals on a hike. Tell them, “poison oak is a dicot angiosperm in the sumac family, Anacardiaceae.” If someone asks you to explain those science-y words, change the subject by exclaiming, “Look! There’s a least Bell’s vireo! Those are endangered! They nest in poison oak.” But be careful. If you have a birder along, they may embarrass you by pointing out that you’re a thousand miles from that bird’s range. Change the subject again by asking if the birder has added one to their life list. (The ensuing disquisition will likely also speed up a lagging hiking group.)

Poison oak’s tiny spring flowers mature into fruit of a type known as drupes. You’re familiar with drupes: plums and apricots are members of the class, too.

Quit complaining. Even though it would perhaps be satisfying were such an irritating plant an invasive, and so justifiably targeted for eradication, it’s actually part of a healthy native ecosystem.

So we have to live with it. Birds and beasts, immune to urushiol, do more than live with it. As many as 50 species of bird dine on the berries, among them robins, towhees, and woodpeckers. Ungulates like deer browse the leaves, which are a source of calcium and phosphorus.

In some traditional Native American medicine, poison oak is used to remove warts.

And another reason to not gripe: you probably brushed up the plant wandering off trail, into habitat (i.e. the home of plants and animals) you’re better off staying out of anyway.

Granted, there are those times bushwhacking is justified, so, here’s some information you may find actually useful:

• Don’t panic: poison oak is not really poisonous, in the sense that it’s likely to kill you. The rash you develop from contact with the leaves or stems is, as naturecollective.org vividly puts it: “nothing more than the immune system gone haywire, fighting some harmless substance, like Don Quixote charging at windmills.”

• The rash can take between eight hours and two weeks to appear! So don’t jump to the conclusion that you’re one of the lucky few not allergic to urushiol if itching fails to fire up immediately after contact. It can occasionally take the form of black spots or streaks, rather than the usual red bumps.

• If you somehow land in poison oak, rinse the exposed area ASAP with soapy water. Then wash your clothes, your pack, and your dog (since of course, he or she was on a leash, and so wound up in the weeds with you).

• Bust out the Benadryl, or other antihistamines, to quell the reaction, and hydrocortisone to soothe the itch (or go with old-school calamine). A cold compress may provide some relief, or a short bath with a half cup of baking soda or oatmeal-based bath balm.