Leaves of Three, Let Them Be!!!!!

Have you seen any of these plants before? Perhaps while gardening, hiking, camping, biking or fishing? Can you identify these plants?

Resources

It is vital to know what these plants are and what they look like through changes in the seasons. Poison ivy appears as a weed with three shiny green leaves and a red stem. It grows in the form of a vine, often along river banks. Poison oak grows in the form of a shrub as has three leaves very similar to poison ivy. The leaves of poison oak may vary from bright green to red; in winter, it looks dead. But, beware: the poisonous, rash-causing oil is always there.

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Poison Ivy

Poison Ivy	Fall	Winter
Winter Roots	Winter Berries

 

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Poison Oak

Spring	Summer	Fall
Winter	New Growth	All Seasons

Urushiol

Rash-causing oil? Yes, Urushiol. It is a light, almost colorless substance found throughout these plants in their leaves, berries, stalks and roots. It oozes out whenever the fragile structure of the plant is traumatized. This oil, which can not be seen easily, settles onto the skin and quickly penetrates. Once out of the plant, the oil rapidly oxidizes and forms a polymer that resembles black lacquer. This black lacquer can be seen on trees during the summer particularly in areas of high wind. It is still active although it is a little recognized source of exposure. Pets are another unexpected source of exposure to poison ivy/oak. The oil attaches to the fur of dogs and cats, who are generally not bothered by it but promptly transmit it to their owners. Exposure to the smoke of these burning plants can also cause a reaction.

Reaction

Poison ivy and poison oak are botanically and chemically related. A person sensitive to poison ivy will also react to poison oak. The skin rash, a form of contact dermatitis, usually develops a day or two after contact with the plants). Things to look for include; itching, redness, burning feeling, swelling and blisters. While annoying, the rash heals spontaneously within a week to ten days, with or without treatment. Most people use over the counter medications to ease the discomfort associated with the rash. There are however, some instances where the rash can be severe, widespread all over the body, and require medical attention.

First Aid

Time is of the essence.

	The skin should be washed with soap and water as soon as possible following exposure. After ten minutes the oils have penetrated and can not be washed off.
	Scrub under the fingernails with a brush to prevent spreading of the oil from touching and scratching.
	Wash the clothing and shoes of the person exposed separately. Oils can linger on these surfaces for days.
	Bathe animals who may have been exposed and can carry the oils on their fur.
	Body heat and sweating can aggravate itching. Stay coo l and apply cool compresses to the skin.
	Calamine lotion may decrease itching.
	1% hydrocortisone cream may be applied to relieve inflammation and itching.
	In children, antihistamines may be useful if given at bedtime since their sedative properties help reduce scratching at night.
	In case of severe or extensive rash, especially around the face or genitals, see a medical professional.

Prevention

Learn to identify these plants and teach your children to identify them as soon as they are able. Avoiding these plants is the best way to prevent poison ivy/oak dermatitis. Remove these plants if they are growing near your home. Cover your skin with clothing ( long sleeves, long pants, socks and shoes) when walking in the woods or areas where these plants may be growing. The use of barrier creams may also be helpful.

Can you become desensitized by taking urushiol by mouth? In a word, no. In 1993, the Food and Drug Administration forced a recall of all such products on the market. However, a small company in San Mateo, California, is working on a preventive vaccine they expect to market in three to four years. Until then, your best course is to stay out of harm's way-or quickly decontaminate yourself if you do encounter the aggravating weed.

Page Revised 03/27/2010