Poison ivy
Poison ivy (also known as rhus or toxicodendron dermatitis) is one of the most frequent causes of skin rash among people who spend time outdoors. After contact with poison ivy, up to 85% of people develop a blistering skin rash. The rash can range from mild to severe, depending on level of exposure and personal sensitivity to the plant. Airborne ashes can get into the eyes, nose, throat and respiratory system can cause problems if the plant is burned. But what is poison ivy exactly? And how can you identify the plant?
What is poison ivy?
Poison ivy is a Native American plant which causes an allergic skin reaction. The plant can be found throughout the continental United States, except in the Southwest and has three characteristic shiny green leaves and a red stem. Poison ivy typically grows in the form of a vine, often along riverbanks.
Poison ivy causes a skin irritation called contact dermatitis that may result in a red, itchy rash of small bumps that can blister or swell. Rashes caused by poison ivy and its cousins (poison oak and poison sumac) generally aren't serious, but can be bothersome. The rash caused by poison ivy does not spread and is not contagious.
Types of poison ivy
Poison ivy, and its cousins poison oak and poison sumac can be identified by characteristic leaf patterns. Each leaf on poison ivy and poison oak has three smaller leaflets, while the middle leaf has a longer stalk than the others. Poison sumac contains a row of paired leaflets with an additional leaflet at the end. Often the leaves have spots that resemble blotches of black enamel paint. In early fall, the leaves on these poisonous plants can turn yellow or red, while fruit turns off-white. Other characteristics of each plant include:
Poison ivy – This weed-like plant grows as a bush, plant or climbing vine. The leaves typically grow three leaflets to a stem and vary greatly in their shape, color and texture. Some leaves are shiny, smooth and elliptical. Others are elongated and toothed with distinct leaflets. In the fall, the leaves may turn yellow, orange or red. In the spring, poison ivy develops yellow-green flowers and green or off-white berries.
Poison oak - Poison oak has oak-like leaves and grows as a low plant, shrub or bush. Like poison ivy, poison oak typically grows three leaflets to a stem.
Poison sumac - Poison sumac is a tall shrub or small tree with two rows of leaflets on each stem and a leaflet at the tip. The leaves of poison sumac are smooth.
Although poison ivy is a nuisance to people, it attracts wildlife. For example, songbirds feed on its berries during fall migration and in winter or on insects hiding in the vines. Small mammals and deer browse on the poison ivy foliage, twigs and berries. So why does the human body react so strongly when it comes into contact with poison ivy? And how can you avoid developing a poison ivy rash?