Are you itching to get outside? (Pun intended :))

It’s that time where we can start planning some outdoor trips to the crag. YAY! I’m super psyched since I feel like this winter has been relentless and I’m in deep need of some warmer weather and some real rock. So, as you start creating your tick lists, it’s also a good idea to familiarize yourselves with harmful plants you could encounter on your way to your favorite project.

Last fall I was exposed to poison ivy and it wasn’t a pleasant experience. Thankfully, my reaction wasn’t too bad but it did stick around for WEEKS!! The reality is all of us climbers are at risk of coming into contact with these plants because they like to locate themselves right where our beautiful climbs are. So do yourself a favor and just take a couple minutes and learn how to recognize the most common poisonous plants so that you can do your best to avoid them. The old saying ‘Leaves of 3 let it be, leaves of 4 eat some more’ is a good start but it’s not enough. Below I’ve listed the 5 top plants you should avoid when venturing out into the wilderness. These plants can be found all over North America, and some can even be found in Asia and Europe. Just make sure to do a bit of research so you know which plants are around the area you plan to be climbing.

1. Poison Ivy

Probably the most commonly known poisonous plant is poison ivy. Unfortunately, poison ivy is a very adaptable plant, which means it can grow in many different environments and can look slightly different depending on where it grows. The leaves are usually shiny, oval shaped, have slightly jagged edges and grow in groups of three on woody stems. They are usually green in the summer and can change to hues of yellow, red, and orange in the fall and spring. Poison ivy can grow low to the ground, as a bush, or as a climbing vine.

Contact with the plant can cause swollen, red, itchy skin and can even start to blister. The severity of the reaction is based on your immunity to the plant. Few people have no reaction at all, but it usually ranges from a mild itchy irritation to a sever large rash. After exposure it can take from a couple hours to as much as a couple days for the irritation to appear and it can stick around for weeks. Not fun.

Outdoor rock climbing Poison Ivy2. Poison Oak

Poison oak has three shiny leaves per stem like poison ivy, except the leaves somewhat resemble oak leaves. The leaves are green and change color with the seasons similar to poison ivy. The stems are usually a brown or gray color and can grow over 6 feet tall. This plant contains the same poisonous sap as poison ivy, so the reaction after contact is the same.

Outdoor rock climbing poison_oak3. Poison Sumac

Poison sumac is another that contains the same poisonous sap as poison ivy and poison oak, however, this plant has a slightly different look. Instead of the typical 3 leaves per stem, poison sumac usually has 7-12 leaves that grow on a red stem. This plant can grow up to 20 feet tall and has smooth edged green leaves that change color with the seasons. Poison sumac is usually found in swampy areas.

Outdoor rock climbing poison-sumac4. Stinging Nettle

Stinging nettle doesn’t even try to look friendly. It’s got jagged leaves that travel all the way up the stem and is covered is fine stinging hairs. It can grow up to 6 feet high. Through contact, it’s stinging little hairs can penetrate the skin and release an irritant that will leave you with a rash. Good news is that it usually doesn’t last very long, but it can be uncomfortable.

Outdoor rock climbing stinging-nettle5. Endangered and Threatened Plants

Lastly, although not poisonous, you should also absolutely avoid endangered and threatened plants. Not only for the obvious fact that they are endangered or vulnerable to endangerment, but also for the fact of avoiding future access issues. It really sucks to have great climbing areas closed down do to the lack of respect for the environment. Regardless of whether it is climbers, or hikers, or tourists, or whatever, it’s important that we climbers continue to do our best to reduce our impact. This includes things like sticking to designated trails instead of bushwhacking your own way through, not ripping out plants if they’re in your way, and only rappelling on specific trees. Be a responsible climber and do some research before heading out to the crag. Find out what endangered plants are in your area as well as what you can do (or avoid) to maintain our climbing areas open.


Poison ivy, poison oak and poison sumac all contain the same poisonous sap: urushiol. The sap can be found in the leaves, stem, roots, and berries of the plant, so contact with any part of the plant can lead to a reaction (even during the winter when just the stems are around). If you realize immediately that you’ve been exposed to the plant, wash the affected area as soon as possible to reduce your risk of getting a rash. If you end up falling victim to these poisonous plants don’t scratch it. Yes, it’s extremely difficult not to (I’ve been there), but at least try. You can relieve the itching with calamine lotion, cool baths (or cold compress), oatmeal baths, or a water and baking soda paste. If your case is sever, you may be in need of some stronger medication, so go see a doctor.


The best way to avoid the misfortune of coming into contact with these plants is to become aware of them as you are right now. However, here are some other tips to keep in mind when venturing out to the crag:

  • cover any exposed skin, especially on your legs
  • try to avoid overgrown trails
  • any clothes that come into contact with poison ivy, poison oak, or poison sumac can still easily transfer the irritants to your skin so it’s a good idea to throw them in the wash afterwards
  • similar to above, dogs can also transmit the irritants to your skin if they brush up against any of these poisonous plants. Be cautious of any dogs you pet if you know you’re in an area that is home to these plants, or if you have a dog, make sure to give him a bath once you get home

 Are there any other plants that you’d like to make climbers aware of? Please share with us below!