Health Hazards » Poisonous Plants

Poison ivy, western poison oak and poison sumac have poisonous sap (urushiol) in their roots, stems, leaves and fruits. The sap is released when the plant is bruised, making it easier to contact Rhus- dermatitis in the early spring and summer when the leaves are tender. Therefore, brushing against an intact plant will not cause a reaction. However, these plants are very fragile. Stems or leaves can be damaged by the wind, animals or insects. The sap (urushiol) may be deposited on the skin by direct contact with the plant or by contact with contaminated objects, such as clothing, shoes, tools, and animals.

Approximately 85 percent of the general population will develop an allergy if exposed to these plants. The sensitivity to the sap usually develops after several encounters with poison ivy, oak, or sumac. Forestry workers even have developed rashes or lung irritations from inhaling the smoke of burning plants.

  • Poison Ivy:
    Grows everywhere in United States except Hawaii and Alaska. In the East, Midwest, and the South, it grows as a vine. In the Northern and Western United States, it grows as a shrub. Each leaf has three leaflets. Leaves are green in the summer and red in the fall. In the late summer and fall, white berries may grow from the stems.

  • Poison Oak:
    Oak-like fuzzy leaves in clusters of three. It has two distinct kinds: Eastern poison oak (New Jersey to Texas) grows as a low shrub. Western poison oak (Pacific Coast) grows to six-foot-tall clumps or vines up to 30 feet long. It may have clusters of yellow berries.

  • Poison Sumac:
    Grows in standing water in peat bogs in the Northeast and Midwest and in swampy areas in parts of the Southeast. Each leaf has clusters of seven to 13 smooth-edged leaflets. The plants can grow up to 15 feet tall. The leaves are orange in spring, green in summer and red, and orange or yellow in fall. There may be clumps of pale yellow or cream-colored berries.

  • Itching

  • Redness

  • Burning sensation

  • Swelling

  • Blisters

  • Rash (may take up to 10 days to heal).

  • Wear long-sleeved shirts and long pants, tucked into boots. Wear cloth or leather gloves.

  • Apply barrier creams to exposed skin.

  • Educate workers on the identification of poison ivy, oak, and sumac plants.

  • Educate workers on signs and symptoms of contact with poisonous ivy, oak, and sumac.

  • Keep rubbing alcohol accessible. It removes the oily resin up to 30 minutes after exposure.