Many Clients and Friends are always asking me about the identification of Poison Ivy and how to treat it. Below is general information I have gathered over the years. Poison Ivy foliage does change shape over time. This could be part of its survival strategy. See info and photos below:
Poison Ivy is a threat all year long since the roots as well as the foliage bear the irritant, but when the plant has leafed out, identification is much easier. Those vines you are pulling out of a shrub, or the shallow roots you are pulling from the ground are probably Poison Ivy. Unfortunately, the Urushiol in the foliage, stems and roots can cause the rash that plagues so many of us. We can all recognize the hairy vines that are frequently winding up the side of a tree. It is the immature vine without easily visible hairs that will fool us every time.
Identification can be tricky. Every year, there are many who insist that the plant with a 5-part leaf is really Virginia Creeper and not Poison Ivy, and every year I have respectfully disagreed…but no longer. A special thank you to Betty Marose, the retired University of Maryland Extension weed specialist and horticulturalist who took the time to forward to me several scientific articles concerning Poison Ivy and Virginia Creeper. My landscape contractors and I have been suffering from a ‘Poison Ivy’ rash for many years after working in areas where the 5-part leaf was prevalent, so you can understand my reticence to accept that this is not Poison Ivy. I have since learned that Virginia Creeper contains OXALATE CRYSTALS that have been known to cause a rash almost identical to that caused by Poison Ivy. In addition, it is common to see Poison Ivy and Virginia Creeper growing side by side in the woods. The message to gardeners is to be cautious when working with either Poison Ivy (urushiol) or Virginia Creeper (oxalate crystals). If you are sensitive to one, you may be sensitive to the other as well.
For help with identification, see the photo below (courtesy of Betty Marose):
Once the plant leafs out, it appears as though the size and shape of the leaves changes over time. Sometimes, it looks as though Virginia Creeper has 5-part, whorled, serrated leaflets, like those above. Be aware that it can morph from 7 to 5 to 4 or even a 3-part leaf. With respect to Poison Ivy, it will always be a 3-part leaf. Sometimes the leaflets have some serration, and in the very mature leaves, the serration will disappear. The photos attached should help you with your identification.
VIRGINIA CREEPER ON FOREST FLOOR
5 -Part, Whorled Leaves, Serrated Edges
MATURE POISON IVY
3 Leaves, Smooth Edge, Hairy Stem attached to Tree, Smaller Branchlets Extending Off
VIRGINIA CREEPER – NEWLY EMERGED PLANT
Notice the first 2 leaves (the cotyledons) are heart shaped. In this example, the next segment to appear has 3 leaves, then 5 leaves.
VIRGINIA CREEPER COLONY
Some Plants Have 5 Leaves, Some Have 3
POISON IVY WITH ENGLISH IVY
The Poison Ivy has the Big Leaves
VIRGINIA CREEPER FOLIAGE
With Red Center Visible
Aerial Tendrils. Notice the Difference in the Leaves.
Even Virginia Creeper Foliage Can Morph.
WHEN YOU GO OUT IN THE GARDEN OR THE WOODS…My recommendation is to wear gloves, long sleeves and pants. If this is too onerous due to the heat, then be sure to wash frequently with cold water and Dawn. Sometimes, I wash my skin with mud as a quick intermediate step. I used to apply Ivy Block before heading out into the garden, but am no longer able to locate this wonderful product. If you know of something similar, please let me know. The Ivy Block lotion would form a protective coating between your skin and the Urushiol.
AFTER EXPOSURE… There is a new product on the market, Zanfel which has been extremely effective after exposure. As soon as I can after exposure, I apply the product creating a paste with a bit of COLD water, and keep massaging until the irritation dissipates.
Simply washing with COLD water and Dawn has worked well for many people.
Some people swear by Technu Extreme after exposure. Annetta says, many have been successfully using Technu Extreme when exposed to Poison Ivy while gardening. Keep a tube in the car, kitchen and shower and apply it after each gardening day as a prophylactic. You can wait up to 8 hours after touching the plant for it to work. Simple Technu does not work as well. The trick is to apply it with a bit of COLD water and to rub it in for 20-30 seconds.
After the rash appears, I use Caladryl lotion which provides significant relief.
Another option after exposure is to apply cold water, Fast Orange and pumice. Fast Orange is relatively inexpensive, and available in most hardware stores. I have a client who swears by this method. Be sure to use cold water to keep the skin pores closed.
After exposure, wash your gloves and boots with dirt to remove the surface oils. Some follow with a Dawn bath, but I never bother. Immediately, wash all of your clothes, and your skin. The sooner you wash, the more diminished will be the rash. The oil will stay active on clothing for hours, so people frequently have secondary exposure which leads them to think that the rash is spreading.
Good luck, and I hope this helps reduce your unpleasant encounters with Poison Ivy.