Friday, May 29, 2009

Nature Guide: Poison Ivy

Following the Landscape Committee's recent move to reduce the use of chemical weed controls in Princeton Landing, residents are reporting more weeds growing on the property, including poison ivy. We asked our Nature Guide Jon Latimer for some information about this noxious plant.

"The leaves of poison ivy contain a colorless, odorless oil called urushiol which will cause an allergic reaction in most people. Brushing or breaking a leaf releases this oil, but it can also be transferred by touching the fur of a dog or cat that has come in contact with it. Even leaves that have been dead for a while may still contain urushiol.

"Urushiol binds to the skin on contact and may cause severe itching which can develop into a reddish inflammation or bumps, then blistering. Left untreated, a rash can last up to four weeks. The best way to deal with poison ivy is to avoid touching it.

"In Princeton Landing plants are being found on berms, in beds and under trees. It is also creeping into the edges of some lawns. Plants can be recognized by their clusters of three almond-shaped leaflets (1 to 4 inches long). It may help if you remember this useful little rhyme about poison ivy: 'Leaves of three, let them be!'

"Leaf color ranges from light green on younger leaves to dark green on mature ones. The leaves have a smooth surface and when they are mature they are somewhat shiny. In fall they turn red. Poison ivy is usually seen as a low ground cover, 4 to 10 inches high, but it can grow into a shrub as much as 4 feet tall.

"Unfortunately, poison ivy often blends in with other plants, so it's possible for you or your pet to come into contact with a patch of poison ivy and not even notice until the itching begins."

For information about treating a rash caused by poison ivy, click here.