Not many things give me nightmares, but poison ivy—Toxicodendron radicans—is one of them.

I didn’t even know what the blighter looked like when I started gardening in New York’s Hudson Valley. Vague ideas of Christmas card’s wreathed in leafy loveliness came to mind, and I imagined some minor skin irritation akin to the hives from a stinging nettle. Boy was I in for a shock.

One night I was awoken by an intense itching on the insides of my arms: I’d met my nemesis. But this noxious weed wasn’t going to get the better of me! I put on my armor—heavy-duty gardening gloves, long-sleeved sweatshirt, jeans, and boots—and waded into battle. I even went so far as to ditch my old clothes once I’d beaten my enemy into submission.

It didn’t help. The urushiol—the toxic sap of the plant—worked its way under my defenses. I looked like a burn victim, with oozing bandages swaddling my arms and shins. And don’t talk to me about the excruciating itch that made me tear at my skin like a mad woman.

I tried every remedy in the almanac—oatmeal baths, jewel weed, calamine lotion, cortisone, baking soda, bleach. Yes, you heard that last one right—neat bleach! They all worked to a degree. But the bottom line is that once the angry rash and blisters appear, you have to resign yourself to three weeks of hell.

So it’s no wonder that walking past a lush patch of poison ivy on the roadside is enough to give me sleepless nights. And when a seedling dares to rear its not-so ugly head in my garden, it makes me break out in a cold sweat and reach for the Round-up.

Recently I learned an even more disheartening fact: A study by researchers at the University of Georgia found that poison ivy is particularly sensitive to CO2 levels, greatly benefiting from higher CO2 in the atmosphere. Poison ivy’s growth and potency has already doubled since the 1960s, and it could double again once CO2 levels reach 560 ppm David Templeton (July 22, 2013). “Climate change is making poison ivy grow bigger and badder”. Pittsburgh Post-Gazette.

So, unless you fancy a post-apocalyptic world over-run with vast jungles of poison ivy, curb your CO2 emissions!