Poison ivy, a ubiquitous woody vine, is responsible for many people avoiding the brushy outdoors. The culprit is a chemical called urushiol. The toxin can bind to skin proteins within 15 minutes. Once that happens, soap and water won’t remove it. How the body reacts to urushiol determines the severity of the dermatitis.
Some people have no reaction at all and are for all practical purposes resistant to poison ivy, oak, and sumac. The same toxin is present in all three, though exposure to poison sumac is much more severe. According to most estimates about one person in 10 is resistant or nearly so.
Here’s where most people get confused. The toxin is present in the plant at any time of the year. It can even be spread by the smoke if plants are burned. Urushiol can be spread from pets and clothing to other people and other clothing that have contacted it. What can’t happen is the toxin cannot be spread from person to person once it enters the body. In other words, once you get the rash you can’t rub it on someone and give them the same symptoms.
There are numerous over the counter remedies to treat the dermatitis, which can last as long as a month. Treatment can be costly and stain clothing. Other solutions might be in your backyard.
Jewelweed, (Impatiens capensis), is very common in moist shady areas around here, usually near water. It has a yellowish orange flower that resembles domestic impatiens. The stems are also brittle and juicy, just like the impatiens in flower gardens. This juice is what will cure the problem.
Crush the stems and rub the juice on the affected area immediately after thoroughly washing exposed skin with soap and water. If soap isn’t immediately available, flush the skin with jewelweed juice. It will help relieve symptoms even after the rash has developed.
If you happen to venture into other parts of the country where poison ivy and its relatives are common, don’t despair. Jewelweed can be found in every state and province of Canada east of the Rockies. Around here it begins to emerge in mid-April and strongly resembles the common impatiens.
There is an old wives tale that states where poison ivy grows so will jewelweed. This is not entirely true. Poison ivy can tolerate much drier soil and sunnier conditions than jewelweed. In these sunny, more open areas there is also another poison ivy solution. Common broadleaf plantain, (Plantago major), also relieves the symptoms of urushiol as well as the swelling and irritation from bee stings. Simply crush the leaves, especially the petioles (stem-like portion of the leaf) and massage the juice into the affected area.
Broadleaf plantain is that ugly lawn weed with the spike-like inflorescence and the rosettes of round to oval leaves that lay flat against the turf. While not a favorite in lawns, plantains are edible as a pot herb and not all that bad when young. Just be careful not to eat them if you have treated your yard with a broadleaf herbicide.
Ted Manzer teaches agriculture at Northeastern High School in Elizabeth City (firstname.lastname@example.org).