The shiny leaves of this poison ivy vine make the transition from reddish to green in the late spring season. KatieDobies / iStock / Getty Images Plus
Poison ivy leaves grow in clusters of three with the middle leaf being slightly bigger than the two on either side. The leaves have veins that are opposite one another, growing upward in V-shaped patterns. Leaves start out reddish in spring, then become a shiny green in summer before turning various shades of red, orange, and yellow in fall. Plants produce small, waxy white berries in late summer that turn red in fall. As the vines age, the stems become woody and put out distinctive “hairy” root growths. Beyond their identity, though, these vines are better known for the irritating rash they can cause.
Poison ivy vines are climbing up a tree. Note that the leaves are in clusters of three. George Weigel
Ben Franklin’s saying, “Leaves of three, let them be,” is good starting advice.
Unfortunately, that turns out to be harder than it sounds for three reasons:
Even further, myths about poison ivy lead to more confusion about how to keep yourself safe from the burning rash of this vine.
The perpetrator in poison ivy is a potent rash-causing oil called urushiol. That oil easily transfers from plants to objects to people – including tools, clothing, shoe bottoms, pets, even stray soccer balls retrieved from a weedy area. Many people get rashes without ever touching or even seeing a poison-ivy plant.
One preventive step is keeping the yard as weed-free as possible.
Others include:
Rashes usually can be stopped if you wash within 15 minutes of contact.
Although Urushiol oil can be found in other plant types, poison ivy is its own unique plant differentiated by the fact that it always has three leaves unlike other Urushiol carriers. VectorMine / iStock / Getty Images Plus
Urushiol oil is in every part of a poison-ivy plant, not just the leaves, and it can remain viable even after plants are dead.
That means you can still get a rash by pulling leafless vines in winter or handling vines after you’ve killed them with a weed-killer. Some people have had their worst rashes in winter.
The rash-causing Urushiol oil can remain viable for as long as five years after poison-ivy plants are dead.
About 85 percent of the population gets rashes from poison ivy.
Some people are more sensitive than others, with ages 5 to 20 being the most sensitive age range. Sensitivity tends to lessen for people from their 30s on.
However, just because you touch poison ivy and don’t get a rash one day, doesn’t mean you won’t get a rash another day. You could get a rash next touch – especially if you get more oil on your skin. In other words, it’s possible for people who never got a rash before to suddenly get one at an older age.
You can’t build immunity by eating poison-ivy leaves either. That’s a dangerous myth that could cause a serious rash in your throat.
One of the worst ways to tackle poison ivy is to cut it down with a string trimmer. That spews oil, throwing it on your clothes and possibly getting it in your eyes or nose.
Worst of all is burning yanked or dead poison-ivy plants. Urushiol oil gets in the smoke, and if that’s breathed, a very painful and possibly even fatal rash can affect your lung lining.
Never mow, weed-whack, or burn poison-ivy plants – dead or alive.
Learn safe techniques for getting rid of poison ivy and further equip yourself to be able to identify the vine.
Despite the ease with which you can get a rash from poison ivy, you won’t get a rash by touching someone’s rash or blisters, which typically occur two to three days after oil exposure.
However, there’s a chance you could get a rash if the person hasn’t washed oil from the skin. The same goes for spreading the rash around your body. The fluid in the rash won’t spread the reaction, but any left-over oil could.
