There is lots of confusion over poison ivy, poison sumac, and its relatives. Even the actual rash that comes from poison ivy contact has many false beliefs. It's not contagious, those seeping, oozing bubbles that make you want to amputate itchy limbs or skin. Relief can be found from various sources, but it's always best to recognize the plant, even to understand what to do once you've touched or brushed against it.
There are 9 species of toxicodendron. The botanical root for the genus comes from Greek toxicos or poisonous and dendron for tree. Our eastern poison ivy, the most common culprit, is Toxicodendron radicans, referring to its vining habit. Within our geographical region, West Virginia and Maryland, you can also find Toxicodendron vernix or poison sumac. In this case the species name is from Latin vagus, meaning wandering, roving or roaming.
As gardeners we are apt to suffer from a reaction to touching the leaves. And it's not actual poison in the leaves, rather an allergen that causes our immune system to react. The reaction is delayed, usually 8 to 48 hours. The good news, sensitivity usually decreases with age and with repeated exposure, although everyone has a different level of sensitivity. Some folks are completely immune to the oil or urushiol in the leaf, I have known people that claimed they could eat it!
The oil is sticky and a reaction can come from the soil it's growing in, or even from petting your pet after they have rubbed against the leaves. It's only humans that suffer from the sticky oil, various mammals eat the leaves and over 60 species of birds consume the seed, hence the random occurrence in our gardens. The stem is hairy, which is one way to recognize the plant, particularly in the winter, when a reaction is just as likely. An old saying warns us; "Leaves of three, let them be. Hairy be wary".
Various remedies for post contact are incredibly effective. Both Tecnu and Zanfel remove the urushiol, best used within 10 minutes after contact, before the oil binds with the skin. Use like a liquid soap, cover your skin, leave it on for up to minute and rinse off. I have been lucky enough to have Tecnu work an hour after contact. Tecnu was originally designed to remove radioactive fallout dust, it's a cleanser. Zanfel binds with the urushiol oil to remove it, effective even after symptoms occur.
Poison ivy is related to cashews, all in the same sumac family. A common misconception; not all sumac are poisonous. With cashew nuts, the outer skin does contain urushiol oil, but when roasted, the oil is destroyed. Note to self; don't roast raw cashew nuts and breath the smoke. The most dangerous reaction to poison ivy or its oil comes from breathing the smoke when burning plants. The lining of the lungs can become inflamed, you can end up in the hospital.
My favorite way to remove the plant is using a long, plastic bag. As I pull the offender out of the ground, I lift the bag to cover the leaves and then dispose of both. Newspaper can be used the same way. Even the slightest touch of a leaf will have me itching, so I keep something available to negate the problem. I've spent too much time suffering from the rash to ask for it again. It must be time for me to be immune, wouldn't that be grand?
