Itching to get into the outback?
Beware the chameleon of forest flora: poison ivy By Dora Boersma
F
ROM OUR CANOE, we spotted the campsite we’d dreamed about all winter. A sandy beach at the mouth of a gurgling river. Dig out the hammock! The same moment our canoe hissed to a stop on the wet sand, our three-year-old son hopped out and checked out every corner of the campsite. As we pulled our sleek craft farther up the beach, we noticed small clumps of plants all over the place. After a closer look, we remembered: “leaves of three, let them be.” Could this be poison ivy? And what’s it doing on a sandy beach? Stow that hammock and let’s push off. The poison ivy leaf usually has three leaflets, but it can fool the unwary by sometimes having leaves in groups of five to nine. It can grow in a vine-like form or as a shrub. The leaves can change colors seasonally and may appear yellow-green in the spring, green in the summer, and red or yellow in the early fall. The leaflets can be serrated with a few or many coarse teeth, or they can even be lobed. It is important not to touch the plant in order to avoid the oil called urushiol, which can travel on anything that brushes against it. Urushiol is a colorless or pale yellow oil that oozes from any cut or crushed part of the roots, stems, and leaves. The oil can stick to shoes, clothes, hands and pet fur, so it’s possible for your skin to come in contact long after your excursion has ended. About 85 percent of people react to the oil with varying degrees of sensitivity. There can be severe itching, redness, and swelling, followed by blisters within 12 to 48 hours of exposure. The rash often has a spread pattern that reveals where the person brushed against the plant. Blisters become crusted in a few days and can take 10 days or longer to heal. In general, people are less sensitive to poison ivy as they get older, so there
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may finally be a benefit to putting a few birthdays behind you! Poison ivy, poison oak and poison sumac are closely related species that can be found in various locations in Canada and the United States. Poison ivy grows east of the Rocky Mountains and poison oak grows in the west and the east. Poison sumac graces the landscape in southern Canada and the eastern United States. The flowers, fruits and twigs of poison ivy and poison oak look similar, and both species can climb tree trunks. Western poison oak needs a lot of water and eastern poison oak likes sandy soil, but occasionally grows near lakes. Poison ivy tends to thrive in well-drained, fertile soil. If you wish to remove poison ivy from an area, don’t burn it—the urushiol can go airborne and may irritate your lungs. And remember, the oil still present in dead poison ivy plants can cause a rash for several years after the plant has died.
Effective first aid
What should you do when you think you have been in contact with poison ivy? The sooner you can rinse off the oil the better. Immediately use lots of cold running water, and follow with plenty of
soap. The oil can be easily transferred from hands to face and elsewhere, so pay close attention to any location that could be affected. Contaminated clothing can be dry-cleaned or cleansed in the washing machine with detergent. Alcohol and water will remove the oil from shoes, tools and other items very effectively. Make sure you wear gloves during clean-up. What about the dreaded itch? Various first-aid remedies are available. Some folks prefer a cool shower followed by calamine lotion. Others enjoy a lukewarm bath with oatmeal or baking soda in it to dry oozing blisters. The blisters do not contain the oil and they don’t play a role in spreading poison ivy to other parts of the body. Oral antihistamines can also relieve the itching. Your local pharmacist might have other remedies if the shower and bath leave you cold. Before your next outdoor adventure, learn how to distinguish familiar varieties of poison ivy from more benign plants. When in doubt, don’t be an optimist. Also, bring along a good bar of soap on all camping adventures. Then, if you do set up your hammock in a lush patch of poison ivy, you can get right into preventative first-aid. —Dora Boersma is a biologist with Environment Canada, and an avid canoeist.
Myth
Fact
If I’m away from home and I am exposed to poison ivy, there is nothing I can do
Not so. Find some water and wash the affected areas, followed by soap—don’t use soap first because the urushiol oil can spread in soap drippings.
Poison ivy rash is contagious
Only the urushiol oil that causes the rash can spread poison ivy. Be careful what you touch and wash as soon as possible.
I can pull out dead poison ivy
The urushiol can stay active for several years after the plant dies.
I can burn the poison ivy on my cottage property
No, the urushiol will become airborne and it can irritate your lungs.
Leaves of three, let them be
A good rule of thumb, but there can be up to nine leaves in a group. Study the plant variations carefully and seasonal colour changes.
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