Danger in the Garden – Poison Ivy

Ken Muellers is an ISA Board Certified Master Arborist and can be contacted at ken@irelandgannon.com.

Would you like to have a plant that has beautiful fall color, lush glossy leaves and can grow almost anywhere? Sounds too good to be true? Well in this case it is just that. The plant I’m speaking of is my arch nemesis, my kryptonite – poison ivy.

I love being outdoors and around nature, but that love and the desire to run though the woods is tempered with the knowledge that Toxicodendron radicans formerly known as Rhus radicans, aka, poison ivy, could be lurking out there waiting for me.

Poison ivy is called “poison” because the oil from the plant, urushiol oil, causes an allergic reaction to most people when they get it on their skin. I say most because about one in six people don’t get a rash from this oil. For the rest of us, the reaction can include an itchy rash that can blister and ooze for weeks after contact.

Many myths about getting poison ivy lurk out there just like the plant itself. First, the leaves are not always shiny and reddish; that’s just typical of the new growth in the spring. Contrary to what many people believe, you will not contract poison ivy from touching someone that has the rash, but you can contract it from touching pets or clothes that have the urushiol oil on them from rubbing against the plant. You can also get it on you from any part of the plant - leaves, stems, roots and berries, even if the plant is dormant in the winter or even if it is dead. And yes, burning it can release the oils into the smoke that if inhaled, can be very dangerous. If you do have the plant on your property, it can be eliminated with careful use of a general herbicide such as Roundup.

If you do have a close encounter with the vine, you want to get the oil off your skin as soon as possible. There are several products including Tecnu and Zanfel that are designed to break up the oil and minimize any reaction. I have heard of (and tried) a wide variety of wacky remedies over the years including bleach, salt water, oatmeal and herbal concoctions. For severe cases, you want to see a doctor who can prescribe medication that should help. Unfortunately, I personally have had little, if any, relief from any of the wacky or professional solutions.

Because contact with the plant can cause problems for so many, it is important to be able to identify it so you can hope to avoid it. Some common phrases to help you that most boy scouts can quote for you are; “leaves of three, let it be” (the leaves are in groups of three on the stems), “berries white, run in fright” (it is one of a few plants with white berries) and my personal favorite, “if it is hairy, be wary” (the vines often have aerial rootlets that look like hairs clinging to the trees). Poison ivy’s two evil cousins, poison oak (T. diversilobum) and poison sumac (T. vernix) are a little harder to identify, but they are also less common. Because I develop a severe case when I come in contact, I’ve learned to spot poison ivy easily. I tell people I can spot it a quarter mile away. That’s probably an exaggeration; my eyesight isn’t what it used to be.

The good news is that although this native plant thrives in many different habitats including sandy shores, woodlands and open fields, poison ivy does not typically grow in elevations above 4,900 feet. So heading to the mountains might provide a safe haven. The bad news is that recent studies show poison ivy thrives in a CO2 rich environment. With climate change speeding along and CO2 levels on the rise, I guess I better get a new prescription for eyeglasses!