Leaves Of Three, Let Them Be: Tips For A Poison Ivy-Free Summer

June 15, 2018 by Lauryn Stalter

Hairy vine, a danger sign.
Longer middle stem, don't touch them.
Leaves of three, let them be.

Parks Conservancy staffers have heaps of simple phrases to help visitors spot the poison ivy that grows throughout our parks. Native to our area, poison ivy (Toxicodendron radicans) provides food and habitat, but can be more than annoying to those of us who have experienced that itchy poison ivy rash. 

Since we can't expect this common native plant to go away - in fact, climate change studies show that poison ivy will get bigger, and more toxic, as carbon dioxide levels rise - we've laid out a few tips that will hopefully keep you poison ivy free this summer.

Hairy poison ivy vines on a tree trunk


Poison ivy can take a few different forms, but a tell-tale feature is the bunching of three leaves. The edges of the leaves can be notched or smooth, and the middle leaf stem is longest. The leaves can appear shiny and have a red node where they meet. 

You may typically notice poison ivy close to the ground, but it also likes to climb trees via "hairy" vines that cling to tree trunks. The ivy's leaves can branch out from this vine and even seem to blend in with the leaves of the tree. It can also grow to knee-height, and we've seen entire tree cages full of shrub-like poison ivy plants.


City of Pittsburgh Department of Public Works crews work hard to keep park trails safe and clear. Avoid contact with the plant altogether by sticking to established trails. 

Dogs that trample through poison ivy can pick up the plant's urushiol oil, passing it to us humans the next time we pet our pups. Keep your dog leashed and close to help keep poison ivy oils from coming home with you. Use a wet cloth to wipe down your dog if you think they've touched poison ivy, or go all in and give them a bath with de-greasing soap such as Dawn.

 Younger and older poison ivy plants


Are you ready to battle the stuff at home? Here's one resource that will help you out; there are many more floating around the internet. We wish you all the best!

Just looking to lay low and stay poison ivy free? Whether you're going off-trail, volunteering with us in the parks, or tackling a particularly wild part of your yard, be sure to wear high socks and long pants. If you're working outdoors, we also recommend long sleeves and gloves. Just like pet fur, urushiol oil can persist on fabrics, so take care when you're changing, and be sure to wash potentially contaminated clothes. Added bonus: these tactics also help to deter ticks!

If you think you may have touched poison ivy, wash up ASAP. Scrub well with de-greasing soap like Dawn, or do as our field staff does and keep poison ivy-specific products like Tecnu close. 

Poison ivy and ticks sound scary, but they shouldn’t keep you from enjoying your parks this summer. Much like wearing a seat belt while driving in a car, taking simple precautions when you’re outdoors will help keep you safe. Staying on trails or wearing long pants when you’re off trails; doing tick checks; and showering when you go home are all habits that we recommend. Preparedness and awareness will make your outdoor time in Pittsburgh’s amazing parks much more enjoyable this summer season.

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