Poison ivy

Poison ivy is a vine that can climb trees.

Photo courtesy Poison-ivy.org

If you break out when weeding, you’re not alone.

Poison ivy is the most common allergic reaction in the country, according to the American Skin Association.

The summer brings more people outside and into nature, just as poison ivy sprouts leaves. Here are tips from Tim Elkner, a horticulture educator with Penn State Ag Extension’s Lancaster County office, on removing the plant, and Dr. Mark Gottlieb, Columbia Regional Health Center, on the medical side of poison ivy’s reaction.

What is poison ivy?

Poison ivy is one of the few three-leafed plants found in yards. As it matures, it becomes a vine and can climb or stay on the ground. At this time of year, the leaves are yellow-green and shiny enough to look oily, Elkner said.

You’ll find poison ivy in areas that aren’t mowed, like a fence row, in shrubs or on the edge of a wooded area.

How should you remove poison ivy?

The main thing to avoid is poison ivy’s oil or sap.

For seedlings, place a plastic bag on your hand and pull out the plant. Peel back the bag over the plant so you don’t touch the plant.

The problem with using garden gloves is that the plant’s oil can get on the glove. If you do something like wipe your brow or scratch your elbow, the oil will spread. So use plastic bags or disposable gloves.

For larger patches, treat the plants with herbicide. Remove after the plant dies. The plants are more susceptible to herbicides in September or October, but you can treat now if you don't want to wait that long.

Another possibility is to cover the plant. Without sunlight, it doesn’t have energy to grow and will die.

How should you dispose of poison ivy?

Place it in a trash can.

Do not compost poison ivy. When turning the compost, you could come into contact with the poison ivy oil.

Do not burn poison ivy. Breathing in the smoke can expose the nose, throat and lungs.

What causes a reaction to poison ivy?

People allergic to poison ivy are reacting to the oil or sap of the plant. The oil is the same in poison ivy, poison oak and poison sumac. If someone has a reaction to one, they’ll usually have a reaction to all three plants.

When someone develops a rash, what should they do?

Get rid of any oil that still might be on the skin, clothing or pets. Wash the rash with lukewarm water and mild soap. Take clothing, shoes and pets exposed to poison ivy and wash with warm or hot water.

Cool compresses and calamine lotion can help.

Oral antihistamines can help you sleep if the urge to itch is too much.

Is it OK to scratch?


“When dealing with a poison ivy rash, the person should not scratch the area, as this can make the reaction worse and break open blisters which can expose the underlying skin to infection,” Gottlieb said in an email.

How long will the rash last?

The rash should be gone in seven to 10 days if you’ve done a good job removing poison ivy oil.

When should someone contact a doctor for their poison ivy rash?

• If severe blistering, swelling occurs. If there’s a reaction with the eyes, throat, lips or mouth.

• If the rash covers a large part of the body.

• If fever develops.

• Or if the rash is not resolving after a week at most.

• If there are any breathing difficulties.

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