Considering how violent some reactions to its oils can be, it’s hard to imagine poison ivy serving any good purpose for anyone.
The English colonist John Smith, in 1609, wrote home about his run-in with this dreaded toxic plant:
“The poisonous weed, being in shape, but very little different, from our English Yvie; but being touched causeth reddness, itchinge and lastly blysters, the which however after a while they pass away of themselves with out further harme.”
Despite the misery it causes, poison ivy does have significant wildlife value, most importantly as a food source. Many small animals and deer are not allergic to it and consume all parts of the plant, leaves, berries, and twigs.
Birds depend on poison ivy berries during the fall and winter months when food is scarce. Furthermore, this plant is very adaptable and can grow as a bush or a vine. Insects use the woody vines as pathways and protective structures up and down trees, and small animals can seek shelter under poison ivy in its bush form.
For these reasons, wildlife groups will never weed it out of state parks and national forests.
That means it’s up to you to know how to identify poison ivy so you can protect yourself from it.
Besides taking precautions with clothing, and staying on hiking paths, it’s best to know what you’re looking for so you don’t stumble into it inadvertently. Poison ivy is a crafty little plant that can grow in several different incarnations.
It can look like ground cover, a vine, or a shrub. It often grows along and over fences with other rambling weeds. The leaves can be smooth and waxy, or they can be dull and rough-textured, with jagged edges. They can grow up to ten inches in length, or they can be as small as an inch or two.
The leaves are red in autumn and when they are young, but they’re green through the summer. As you can see, it can be a very confusing plant to identify. But here’s something to look out for: all poison ivy, no matter the leaf size or color, has three leaves per stem.
Two of the leaves are opposite one another and growing in different directions. One leaf is at the top and has a longer stem than the two side leaves. Remember the old adage, “Leaves of three, let them be,” and leave the playing in poison ivy to the wildlife.
