Poison Ivy

photo by Dave Powell, USDA FS CC BY

Poison Ivy, as its name indicates, contains a poisonous resin. Touching any part of the plant can cause a reaction, including itchiness and blisters. It can be found in all parts of Canada and the United States apart from Newfoundland and California. It is commonly found at forest edges or clearings as well as along fences, roads, or railway lines.

Poison Ivy’s leaves consist of 3 almond-shaped, pointed leaflets ("leaves of three, let it be") that are red in the spring, green in summer, and yellow, orange, or red in the fall. The middle leaflet has a longer stalk than the two side ones. The leaflets can have either notched or smooth edges.

Poison Ivy can grow as a shrub or as a vine, attaching itself firmly to a tree or post. Clusters of cream-colored flowers can be seen in June/July, turning to waxy, pale-colored berries in September.

Did you know? The poisonous resin helps the plant to retain water and was not designed as a defensive measure.