How To Spot Poison Oak On The Trail

For most people, poison oak (or its relatives, poison ivy and poison sumac) mean only one thing: a red, itchy and sometimes painful rash. The common three-leaved plants contain urushiol, an oily organic compound that triggers an allergic reaction in areas where it touches the skin. According to the Agriculture & Natural Resources Division at the University of California only a small percentage of us – 15 to 20 percent – aren’t allergic to it.

There are two species of poison oak: Toxicodendron pubescens, or Atlantic poison oak, and Toxicodendron diversilobum, western or Pacific poison oak. Both earned the names from their oak-shaped leaves. They’re a woody shrub or vine in the sumac family.

Native to western North America, poison oak has a wide distribution, extending from British Columbia to the Baja California peninsula. You’ll find it in various habitats. It thrives in shady and dappled light, and in its vine form it can climb up tree trunks into their canopies. Widespread, poison oak is also in areas including open woodlands, grassy hillsides, coniferous forests, and in tangled shrubs and thorny bushes.

Without question, the best way to prevent poison oak rash is by learning to recognize the plant when you see it and avoid any contact with it. Here’s what you need to know before you hit the hiking trails this year.

What Does Poison Oak Look Like?

First, the leaves usually consist of three leaflets with the central leaf stalk being the longest. Occasionally you’ll spot leaves with additional leaflets, but this isn’t routine.

Poison oak leaves will alternate on the stem. Each leaflet is one to four inches long with lobed edges. They generally resemble the lobed leaves of an oak tree, though poison oak tends to be more glossy in appearance. As with most plants, the color of the leaves changes with the seasons.

Poison Oak Pictures

Young poison oak - Care2

(Photo: Alan Schmierer)

A young poison oak plant.

Flowering Poison Oak - Care2

(Photo: ap2il)

In spring, poison oak plants produce small, white-green flowers. Pretty, but still poisonous.

Poison Oak

Poison oak leaves are bright green during spring and summer.

Poison Oak

(Photo: Thinkstock)

In the fall, the leaves will turn bright red or pink.

Poison Oak with Berries - Care2

(Photo: Jacki Dee)

When fertilized, they’ll also develop into greenish-white or tan berries.

How to Treat Poison Oak

If you are part of the 80 percent of people who are allergic to poison oak, you can expect to see signs of an allergic reaction to appear within one to six days after exposure. Most of the time though, you’ll notice it within the first 48 hours.

Most often, the allergic reaction is a skin rash called dermatitis. It starts out as a minor skin irritation with some stinging and itching. Then, a red rash will break out on the skin. Bumps begin to form which eventually turn into oozing blisters. Typically, poison oak rash can last up to two weeks. In rare instances, it can last much longer.

Obviously, getting a poison oak rash is no fun. But if you’ve accidentally been exposed to the plant, and you have poison oak rash, there are a few things you can do to help relieve the itchiness.

First things first, wash up. Because the oils from the plant can remain on fabric and other materials (and give you another rash!), you should wash your clothes and anything else that may have come into contact with the plant. Wash your body with lukewarm water and soap. Spend extra time on your hands, fingernails, and whatever exposed skin that may have touched it. Resist the urge to touch any blisters that form. Touching them can result in infection.

To manage the itchiness from the rash, try these home anti-itch remedies:

  1. A 30-minute soak in an oatmeal bath is the classic anti-itch treatment. Grind one cup of rolled oatmeal in a blender or food processor until it’s a fine powder. Then, wrap the oatmeal dust in a cheesecloth (a clean nylon stocking works well here) and tie it to the water spout on the tub so that the bag is under the running water. Fill the bath and soak your itching away.
  2. Make a white vinegar compress. Start by mixing a half cup of white vinegar with a pint of water and placing it in the refrigerator to get cold. Once cooled, soak a clean cloth with the vinegar solution and apply it to the rash.
  3. Soak in salt-water. Epsom salts can help the rash dry out.
  4. Some people swear by using lemon juice as a natural astringent to the oily urushiol. You must apply the lemon soon after being exposed and before the oil has a chance to soak into your skin.
  5. Aloe Vera, naturally.

Have you ever had an experience with poison oak? Do you have a favorite home remedy? Tell me about it in the comments.

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Photos via Thinkstock and Flickr


Marie W
Marie W4 months ago

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Jaime J
Jaime J9 months ago

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Leo C
Leo Custer9 months ago

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Joemar K10 months ago


Chrissie R
Chrissie R10 months ago

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Caitlin L
Caitlin L10 months ago

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Janis K10 months ago

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iskrica knezevic
iskrica knezevic10 months ago

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Danii P
Past Member 10 months ago

Thank you for sharing

Danii P
Past Member 10 months ago

Thank you for sharing