As a Northern California native and unofficial beach bum, I consider the inner coastal area from San Francisco to Crescent City my personal playground. On a recent trip to the Mendocino Coast for a little abalone diving and camping, springtime was abloom and abundant. Bright fuchsia foxgloves, golden California poppies and tiny blue columbines dotted my inclining beach trails. And poison oak – it was everywhere.

As wise as we like to think we are about pointing out poisonous oak, ivy, and sumac plants, we aren't immune to its itch. I earned a case of the stuff this last trip that has kept me scratching my limbs – and head in bewilderment – as to how my college forestry studies could educate but not armor a body. Can outdoor enthusiasts truly get away scratch-and-scotch-free from this bothersome botanical family?

WHAT ARE POISION OAK, IVY AND SUMAC?
Your first line of defense is plant identification. The plants are found just about everywhere in the United States, omitting Alaska and Hawaii (as well as some desert regions).

• The lobed three-leaflet oak grows primarily in the West as a scrub, favoring wet or costal terrain and climate.
• Ivy grows as a vine in the East, Midwest and South, reaching as high as seven feet and is also distinguished by a three-leaflet pattern, with one leaflet at the end of the stalk.
• Sumac is found in bog-like standing water in the Northeast and Midwest, as well as swampy areas in the Southeast. It is composed of 7 to 13 leaves – always an odd number.

Keep in mind when the term leaf or leaves verse leaflet is used above. Leaflets are compound – that means there are several (in this case, three) distinct leaves on one stem with a bud at the connecting base of the twig or branch. Leaves are simpler – or just think singular. It would be very easy to confuse poison oak leaflets with, say, coast strawberries, which is exactly what I did in my case.

If you can pick out the poison oak from the berry bush, you did better than I did. Photo by Katrina Ramser

The highly toxic substance on the plants is called urushiol (pronounced oo-roo-shee-ohl). Mainly colorless and sticky, it is found in the oily sap of not just the leaves, but the flowers, fruit, stem, bark and roots. Urushiol is an extremely potent poison – enough so that just one ounce could potential affect every human being on earth. The sap never dries out and lasts for decades.

HOW YOU KNOW YOU HAVE IT?
It takes just ten minutes for urushiol to penetrate the skin. Then 12 to 48 hours later, you get your reaction. First comes the itching sensation, followed by swelling and redness and finally, blisters.

Poison oak, ivy or sumac rashes form as a raised and shaky line, sort of like a trail road you'd find on a backcountry map – or what it felt like when that branch swiped your arm or face.

Contrary to popular belief, the American Academy of Dermatology (www.aad.org) reports the rash does not spread by touching the infected areas. It seems like that’s exactly the case when you discover new breakouts on your body. What's really happening is that when urushiol is exposed to thicker skin (forearms, legs, and middle body), it takes longer for the skin to absorb the poison. Thus the rash continues to pop up.

It's your proneness to poisonous plants that determine the severity and contagiousness of your case – combined with your thoroughness of ridding urushiol. Let's see how you stack up to the Do's & Don'ts of Poisonous Plants & Rashes.

A case of poison oak about 48-hours after initial exposure to the plant. Photo by Katrina Ramser

DO'S & DON'TS OF POSIONOUS PLANTS & RASHES
DO

• SHOWER WITHIN TEN MINUTES OF EXPOSURE. Soap is totally useless after that time span expires. Scrub and lather your skin with laundry detergent.  Remember close contact is defined as direct, indirect, and within vicinity for airborne urushiol particles to attach.
• WASH AFFECTED PETS & CLOTHING. The poison doesn't have an affect on dogs, but fir or cloth acts as a carrier and can be passed through petting and touching. Clean leather boots with water and alcohol.
• PACK A FIRST-AID KIT WITH CALAMINE. Gone are the days of the big calamine lotion bottle with the cotton balls – get yourself a 1-ounce tube of Aveeno anti-itch cream with natural colloidal oatmeal.
• TRY SIMPLE HOME REMEDIES. Aside of the obvious calamine, aloe vera or a paste made of baking soda or cornstarch and water relieves burning and itching. Both goldenseal and tea tree oil are great for disinfecting and improving skin conditions. Even cold watermelon rinds can help reduce the swelling.
• TAKE LOTS OF VITAMIN C (WITH FLAVONOIDS). Vitamin C is a natural antihistamine that reduces swelling. 

DON'T

• SCRATCH. Only urushiol can spread the rash, and it is not found in open blisters. The toxin remains on improperly washed clothes, skin and fir, which if touched can spread to others or yourself for years to come. However, bacteria under your fingers can infect the rash, causing it to look like it has spread.
• ASSUME YOU CAN IDENTITY THE PLANTS. In other words, you've got to know, or you'll assume your hands, clothes, and general touch are all toxin-free. It's a clever little plant that changes into many colors and produces berry-like fruit.
• BURN THE PLANT. You might have a big bushel of the stuff growing on your property and wish to dispense of it. A reaction can develop through inhaling the smoke. For ways to get ride of the plant properly, visit the U.S. Food and Drug Administration site at www.fda.gov.
• EAT THE PLANT. Internally digesting the plant as a form of immunity is an Old Wives' Tail. This isn't like stinging nettle, which sold in capsules or as a tincture is great for allergy sufferers because it contains antihistamine properties.  

COMBATING NATURE WITH NATURE
The good news is the older you get, the less sensitive you become. Maybe that's why my current rash is not nearly as bad as I remember during childhood: It used to get so bad on my face that my eyes would be swollen shut.

The healing of the rash begins around the second day after appearance and when the blisters stop oozing and start crusting. Most bodies are healed within seven to fourteen days.

Prevention is your best defense. Of all the forestry textbooks I laid hundred of dollars down for, my favorite to this day are the pocket-sized Nature Study Guides found on Amazon or Barnes & Noble. For around $3.50 apiece, you can conveniently key-out the bush, berry or tree in question. Set up like those Choose Your Own Adventure children series books, you begin with the leaves or needles and follow simple symbols to different pages in order to end up at a proper diagnosis for your flora or fauna. It's actually a lot of fun for the whole family or a group of friends.

But if the leaflets you are holding are poison oak, ivy or sumac, there is no flipping back and starting over. These resilient and deadly plants can fool or find you anywhere. Happy hunting (and avoiding)!

If you loved these series as a kid

You'll love these Nature Study Guides that help you figure out the plant in question

Baking soda, laundry soap, aloe vera and calamine are just a few examples of simple rash remedies. Photo Katrina Ramser