Q. How do I identify poison ivy and what can I do about it?
Poison ivy (Toxicodendron radicans) is a flowering plant of the cashew family (Anacardiaceae). Along with many other members of this family it produces a very skin-irritating substance (urushiol) in its sap.
Identifying poison ivy: Often-heard advice about poison ivy is “Leaves of three, let it be." In botanical terms poison ivy has compound leaves with three leaflets; nevertheless this a good start to identifying the plant. Poison ivy can be confusing to identify as it can grow as a low-growing ground cover, as a shrub, or as a vine. Moreover, there are a number of other plants that look similar to poison ivy. These include Eastern box elder, fragrant sumac, poison oak and kudzu (not found in the Northeast). It can also be confused with Virginia creeper which usually has 5 leaflets but sometimes has only three. See this native plants website for good pictures which will help in identification.
How to avoid problems with and then treat poison ivy: First, learn to identify the plant and, if possible, avoid it altogether. If you come in contact with it, you should treat the problem as soon as possible:
- Wash the affected area with warm soapy water. If large areas of the body were in contact with the plant, take a shower.
- Avoid rubbing the eyes.
- Apply over-the-counter cortisone cream or calamine lotion for a few days.
- Consider taking an over-the-counter antihistamine pill.
- Apply cool compresses periodically to the affected area.
- Do not scratch, even though the skin may be very itchy. Do not burst any blisters that may form.
- Wash any clothes that came in contact with the poison ivy plant separately.
How to eradicate poison ivy from a garden: The best way to remove poison ivy is to dig it up. Before you start, protect yourself from exposure to the poison. Tape pants closed around the ankles and tape a long-sleeved shirt at the wrists. Wear thick work gloves and protective goggles. If the ground is very dry, water the area first. You can then pull the plants up from the roots by pulling on the thickest stems. Sometimes you will need to dig up any remaining roots separately. Place the plants in a thick-walled plastic bag and place this inside another plastic bag. Dispose of the bag in the household waste. Do not burn the plants or place in the compost. When you are finished, wash yourself with soapy water and wash your clothes separately. It is difficult to eradicate the plant completely; the procedure may need to be repeated several times.
For tips on a variety of gardening topics, see our Plant Information Guides.
- Courtesy of NYBG Plant Information Service