Wednesday, July 7, 2010

The Landscaper's Bane: Poison Ivy

Poison Ivy: the mortal enemy of green thumbs everywhere. Every landscaper, gardener, dude who’s weedeated in shorts, and kid who’s played in the woods has inevitably encountered poison ivy, Toxicodendron radicans. And boy they knew about it!
Interesting facts you may, or may not know:
  • You grew up hearing your mother say ‘leaves of three, let it be!’ She was mostly right! Poison ivy always has a compound leaf with 3 leaflets, though other plants also have this leaf arrangement.
  • It spreads by reseeding- birds love the berries so they are carried far and wide, by creeping roots, and vines that put down roots as they grow.
  • It can be a creeping or climbing vine or a shrub.
  • It has oil that causes the rash when you contact the leaves, and if you encounter the roots or cut the stem, you’re in a heap o’ trouble cause that releases a crap-ton of oil.
  • Some people say they’re immune… they just haven’t gotten it yet. I do admit that there are, obviously, varying degrees of susceptibility.
  • If the oil stays on your skin for longer than a half hour, you’re doomed.
  • The oil on surfaces such as your gloves, clothes, or garden tools can be just as potent years later as if you’d just touched it.
  • You can get it in the winter even though it doesn’t’ have leaves.
  • If you burn poison ivy and inhale the smoke… well, I’ll send flowers. (It can be fatal in severe cases but it’s likely you’ll survive with some severe lung irritation and an ER visit.)
  • If you come in contact with poison ivy, wash in cold water with a dish soap to remove the oil.  Warm water will open your pores and allow the oil to penetrate... not good.
  • No creatures besides humans suffer from the rash from poison ivy.

 A similar plant to poison ivy is poison oak. I grew up with my mother telling me that 5 leaves was poison oak. What she thought was poison oak was really Virginia Creeper- Parthenocissus quinquifolia, bottom photo, which is completely harmless (See update below).  Poison oak is Toxicodendron pubescens, top photo. and looks nearly identical to poison ivy, but does not climb and grows only in shrub form. It also has more deeply lobed leaves.

What to do when you get the rash from poison ivy or oak:
  • If it is severe or on your face seek medical attention. 
  • There are several prescription or over the counter topical creams to aid the healing.
  • Don’t pop the blisters. The juice won’t make it spread, but it’s gross. It could also get infected.
  • Hot showers can ease the itching for several hours… it also feels instantly better. Run the water as hot as you can stand it and let it run over the rash, it burns, but at least it isn’t itching!
  • Go to the beach. That salt water does amazing things… rubbing alcohol also dries it up pretty well.
Well, there you go: some interesting tidbits on your favorite plant to hate, poison ivy.

Oh, wait.  How do you get rid of poison ivy growing in your yard?  See below. 

Seriously though, several applications of a non-selective or a broad-leaf weed killer should do the trick.

UPDATE:  Thanks to the heads up from a reader I've done some research and it appears that while Virginia Creeper doesn't have the rash-inducing oil on its leaves like poison ivy, it is fairly common for people to have a severe allergy to it.  So, pull Virgina Creeper with caution.  I've never gotten this rash, but apparently it happens.

Jessica Watters, GCLP                             Horticulture Technician, Chattahoochee Technical College


  1. Thank you for this helpful information. I have also though that poison ivy was 5 leaves, also. Guess that is what I have been told from my mother, as well. I really enjoy reading your articles and find them very interesting.

  2. I strongly disagree with you about Virginia Creeper. I my area of Maryland this stuff takes off anywhere it can. Telebhone poles, fences, any where there is a bit of open soil. Tearing it out leaves me and mot everyone I know with a horrible rash. Blisters, that join, massive puss bubles. I did some research and I have found that many people get a rash from this plant. For some it is very severe and for others no reaction at all. I caution you about saying it is harmless, If you do not have a reaction it is harmless. If you do have a reaction, like me, the reaction is similar to poison ivy or poison oak but is my case three times as bad and lasting 5 times as long. I realsize this technically is not someone getting poison ivy but it is just as bad if not worse

  3. Interesting, thank you for the feedback. I have never heard of anyone having that reaction to Virginia Creeper before.

  4. My husband ended up on a two-week course of oral steroids from pulling Virginia Creeper off our garage. Stay away from that stuff!

  5. I second the Virginia Creeper information. I have to be extremely careful of it. Hubby has to pull it out for me. He's not allowed to touch anything in the house, front door included until he's scrubbed his hands and arms and changes clothes turning them inside out. I am so severely allergic I end up with it spreading and getting worse each time. The last time I got it on about 75% of my body. The next time I will end up in the hospital from it. It's actually just as common for people to be allergic to it as Poison Ivy, Oak and those in the same family. We always thought it was Sumac until I realized what it was just recently. So please, most definitely don't tell people it's harmless. It can be very dangerous to those with health issues. Especially me. I have severe asthma as well and use oxygen for it. Hence the serious precautions if hubby has to remove it for me.