Ask a Master Gardener
News-Leader March 3, 2013
Question: I have had family members experience the painful consequences of coming into contact with poison ivy. Any advice on how to recognize poison ivy? — B.C. Ava
Answered by Master Gardener Anise Butler:
Poison ivy, poison oak, and poison sumac are all plants that can cause a skin rash when our skin comes into contact with any part of the plant.
The culprit in the plant is an oil, called urushiol, which is present in all parts of the plants. Urushiol is an allergen, so the rash is actually an allergic reaction to the oil in these plants.
Not everyone is allergic to the oil, but many people find they will get the rash even if they have touched articles that have come into contact with it like clothing, hiking gear or gardening tools.
The reaction to the plant will be a rash with red streaks, bumps, blisters and always an awful itch.
Treatment at home for poison ivy includes washing the area with a strong soap like Fels-Naphta and using cool baths and cool compresses to relieve any pain, calamine lotion and even over-the-counter antihistamines.
If the reaction is severe, a doctor should be consulted. The best way to avoid getting into poison ivy is to learn how to recognize it and avoid it. The poison ivy plant has three leaves that will many times appear glossy.
Most poison ivy leaves have smooth edges, but a few may be somewhat jagged and have some color (other than dark green) to them, especially on new growth.
A good comparison with poison ivy is Virginia Creeper. Many people mistake Virginia Creeper for poison ivy, but poison ivy has only three leaves, and Virginia Creeper has five leaves. Both are vine and grow on trees, but poison ivy will hide among other plants on the ground and on trees.
Remember the adage, “leaves of three, let it be.” If you must be around poison ivy, dress accordingly to cover as much of the skin as possible.
Readers can pose questions for the Ask a Master Gardener column that appears in the Sunday edition of the Springfield News-Leader or get more information by calling 417-881-8909 ext 320 and talking to one of the trained volunteers staffing the Master Gardener Hotline at the University of Missouri Extension Center in Greene County located inside the Botanical Center, 2400 S. Scenic Ave., Springfield, MO 65807.