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How to identify 3 poisonous plants

Aug. 10, 2019—Are you looking to head outdoors for some camping or hiking? Just be sure to look out for a few poisonous plants—namely, poison ivy, poison oak and poison sumac.

A close brush with one of these pesky plants wouldn't be fun. If you come into contact with one, it may release an oil called urushiol that can get on your skin and cause an itchy red allergic rash with bumps and blisters. (The rash is not contagious, but beware of any oil on clothing, pets or other items that came in contact with the plant.) And if you burn one of these plants, the smoke could irritate your lungs.

Poison ivy, poison oak and poison sumac thrive in many areas of the country, even in some backyards. And since most people are sensitive to them, it's important to know what they look like so you can avoid them.

Leaves of three

You may have heard the saying, "Leaves of three, let it be!" It can help you remember what poison ivy and poison oak (though not poison sumac) look like. But keep in mind: Poison ivy and poison oak plants sometimes vary, so don't rely on this rule alone.

Poison ivy can be a ropy vine or a low-growing shrub, depending on the variety. The leaves grow in clusters of three. They may be shiny green, turning red in fall. The plants may have yellow or green flowers and greenish-yellow, white or amber berries. Poison ivy grows across the United States, except in Alaska, California and Hawaii.

Poison oak grows as a shrub with leaves that form groups of three. The Pacific variety may grow as a vine. This plant grows primarily in the Southeast and on the West Coast. Look for yellow or green flowers and green-yellow or white berries.

Poison sumac often grows as a woody shrub or small tree in wet areas. Each stem holds 7 to 13 leaflets that are green in summer, turning yellow, orange or red in fall. There may be yellow-green flowers with clusters of whitish-green, pale-yellow or cream-colored berries. Poison sumac is abundant along the Mississippi River and in the boggy areas of the Southeast, but is also found in Northeast wetlands.

Visit the Centers for Disease Control and Prevention website to find out if any of these plants could be growing on your favorite hiking trail.

Treatment

Avoidance is your best defense. But what if, despite your best efforts, you do come in contact with poison ivy, poison oak or poison sumac? First, wash your skin with cool, soapy water as soon as possible to remove the oil. Do your best to scrub under the nails, too, where the noxious oil may be trapped.

To ease the itch:

  • Apply wet compresses.
  • Use an over-the-counter calamine lotion or hydrocortisone skin cream. Be careful to avoid getting these products on areas with broken blisters.
  • Take a soothing colloidal oatmeal bath.
  • Ask your pharmacist about an over-the-counter antihistamine.

If the rash covers a large area or spreads to the face or genitals, see your doctor. If there are signs of a severe allergic reaction—such as swelling of the face or difficulty breathing—call 911 or go to the emergency room.

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