Posted: January 25, 2022
This may seem like a strange time of year to talk about poison ivy, but, really, it isn't. Did you know you can still get it if the plant has no leaves? Or even if the plant is dead?
Leaflets of Three, Let It Be (photo by Margaret Stoddard, Adams County Master Gardener)
Almost everyone knows how miserable a case of poison ivy can be. This may seem like a strange time of year to talk about poison ivy, but, really, it isn't. Did you know you can still get it if the plant has no leaves? Yep. Or even if the plant is dead! Some of the worst cases of poison ivy have occurred near the end of winter, when a person gets a fairly warm day to work outside, and decides it is a great time to clean up that brush pile. Even worse, is when they decide to burn the pile!
Poison Ivy is a native vine. It produces white berries in the fall and is a valuable food source for birds. They love to eat the berries and are responsible for spreading those seeds around our gardens.
I garden in a residential area where I would rarely ever see poison ivy. But in the spring, I find young seedlings popping up in my gardens, usually under a tree. Thank you, Birdies!
Identifying and avoiding poison ivy was ingrained in me when I was young by the Girl Scouts. I guess I grew up thinking it was just a common knowledge thing, so it has surprised me during my adult years that so many people don't seem to recognize it.
There is an old adage referring to it: "Leaves of three, Let it be." If you relied on that and nothing else, you would be running from many plants in your garden! Once you know this plant well, it is very easily recognized and not easily confused with other similar-looking plants.
According to Purdue University, for the adage to be botanically correct, it should be, "Leaflets of three, Let it be." The vast majority of all leaves are simple leaves. Each leaf is attached to the branch by a petiole (many people call it a stem.) A compound leaf is divided into several leaflets all attached by the same petiole to a branch. So, in the case of poison ivy, one leaf actually has three leaflets. Those leaflets are usually a shiny, waxy, green color. They are also usually pointed with jagged edges. To me, the leaves also have a corrugated look to them. Poison Ivy is a vine that likes to scramble up trees and sides of buildings. It sometimes also grows on the ground forming a ground cover, or it can grow in shrub-like form.
Another native plant, Virginia Creeper, is a poison ivy look-alike except it usually has five-leaf leaflets. Virginia Creeper is actually a valuable, non-poisonous plant which is sometimes used in landscaping projects. Both plants turn bright red in the fall.
The stem of poison ivy, which is covered with hairy roots, can grow quite large and thick in diameter in old, well-established plants. At that point, it is very difficult to eliminate. I keep an eye out for them in the early spring because I DO NOT want them to become large. I save the plastic sleeves our newspaper comes in. I pull one over each of my garden gloves to cover my whole arm before I dig the little thing out with my garden knife, making sure I get the root. While grasping the plant with the plastic sleeve I turn the sleeve inside out pulling it off to encase the offending plant, and head straight for the trash can. (It's actually the same action you use when cleaning up after your dog.)
For most people, a case of poison ivy is just an inconvenient, uncomfortable nuisance, but for some, it can be a severe medical problem that requires hospitalization, or at least a doctor's visit to obtain prescription medication.
The rash that poison ivy produces is caused by your body's reaction to something called urushiol oil which comes from the plant. The same oil is also produced by both poison oak and poison sumac. It is in all parts of the plant including leaves, stems, and roots.
Usually, you get the rash when you brush against the plant itself, or something (like your dog) that has already brushed it and is still carrying the oil. One of the worst ways to get it, as mentioned earlier, is when someone burns it, and the smoke goes into your lungs. Remember, urushiol oil is still present even in dead plants.
You cannot get it by touching your own or someone else's rash. The rash is a skin reaction, it does not contain the oil. So you don't spread it by scratching or showering. Sometimes the rash is so bad that blisters are produced. When those blisters break, liquid sometimes is released. That liquid is NOT contagious. Again, it is simply part of the body's defense.
If you are aware that you have come in contact with poison ivy, wash it off as quickly as possible. But remember, it is oil. Warm water will simply spread it over a larger surface. You need something to cut that oil. Thanks to the Girl Scouts, I learned to always keep a bar of Fels Naptha Soap for just such emergencies. Use it with cold water. It will remove the oil from your skin and prevent, or at least lessen, the rash that will form in two to four days after exposure. It also works on your dog.
If you do develop the rash, cover it with Calamine lotion to help dry it out, and reduce itching. Check the drug store for other effective poison ivy combatants. But … a better plan is to learn to recognize this native vine and get rid of it Pronto!
Barb Mrgich is a Penn State Master Gardener from Adams County. Penn State Cooperative Extension of Adams County is located a 670 Old Harrisburg Road, Suite 204, Gettysburg, phone 334-6271.
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