Lawn & Garden
AUBURN UNIVERSITY, Ala. – Leaves of three, let it be. This saying is playful, but poison ivy and poison oak are no laughing matter. Contact with these plants can result in discomfort and itchiness for an extended period of time. Identification, avoidance and potential treatment are important skills to know when it comes to poison ivy and poison oak.
“Poison ivy and poison oak are identifiable by their three leaflets,” said Nancy Loewenstein, an Alabama Cooperative Extension System forestry and wildlife sciences specialist.
People can also identify these plants by the jagged teeth along the edges of the leaflets. The leaflets will be more rounded in poison oak and more pointed poison ivy.
Poison ivy grows in the form of a vine that often runs along the ground or up the side of vertical surfaces such as houses or trees.
“These vines could often be described as ‘hairy’ because of small roots extending from the vine,” Loewenstein said.
Poison oak grows more in the form of a shrub with leaves crowded near the tips of the stems. Clusters of small, lightly colored fruit grow on both plants.
Avoidance and Control
According to Loewenstein, poison ivy is especially common in wooded areas, urban green spaces and along the edge of forests. Poison ivy is most prominent in scrub oak forests, dry pine and other dry sites.
If it is necessary to be in areas where contact with these plants is a possibility, make sure to wear long pants and close-toed shoes, apply preventative lotion and wash the clothes immediately upon exposure.
Controlling and eliminating growth of these plants are also important factors in avoidance of these plants. While burning these plants may seem tempting to remove them from the yard, it is not a good idea.
“Urushiol will become airborne in the smoke,” Loewenstein said. “Inhalation may cause severe swelling of the esophagus and respiratory passages, resulting in difficulty breathing and potentially death.”
Use of an herbicide spray is an effective and safe way to control these poisonous plants. Following instructions on the packaging of these sprays is crucial to application.
“Take the utmost care that no urushiol particles are inhaled if it becomes necessary to cut poison ivy vines,” Loewenstein said.
Painful blisters may accompany a red and itchy rash upon contact with poison ivy or poison oak. Individuals with mild cases can use hydrocortisone or anti-itch creams to sooth irritation. Using oral antihistamines and calamine lotion can also provide relief from the reaction. Few people will react severely enough to require medical treatment. This is usually in the form of injected or oral low-doses steroids administered by a doctor.
More information is available in the Alabama Extension publication Touch-Me-Nots: Poison Ivy, Poison Oak and Poison Sumac. For further information, contact the forestry, wildlife and natural resources regional agent in your area or visit the Alabama Extension website at www.aces.edu.