Nature Notes – Issue 08

Leaves of Three

by Jill McDonald
Poison Ivy showing off Three Leaves, Photo by Jill McDonald.

“Leaves of three, let them be!” as the saying goes. This phrase is simple, yet can be very beneficial to remember to help you enjoy your time outdoors this year. 

What is the culprit at stake? Of course poison ivy would be the correct answer. However, poison sumac and poison oak may also come to mind. Poison oak has leaves of three like poison ivy, however it’s a small shrub found in the Western and Southeastern U.S.A. Here in Southwest Michigan, it is especially good to be aware of poison ivy and poison sumac.

Poison ivy can be a deceiving plant. It is a deciduous plant, with leaves changing colors through the seasons and falling off by winter. The leaves are red in the spring, green during summer, and can be red, yellow, or orange in autumn. They can grow on the ground or as vines up a tree. The plants also produce white berries in autumn. (Note: Vines with leaves of five are typically Virginia creeper.)

Unlike poison ivy, poison sumac is a small, woody shrub and is found in wet areas. It has compound leaves, with 7-13 leaflets, making the leaf feather-like in appearance. Its berries are green to white, compared to the bright red berries of non-poisonous regular sumac.

Unfortunately these plants get a bad rap, due to often causing a rash when exposed to the plant’s resin of Urushiol oil. Urushiol can remain active for up to five years, even in dead plants. Burning of these poisonous plants is not advised, as airborne particles of the oil can spread, causing severe allergic respiratory problems.

Although these plants may seem like an annoyance, they are actually beneficial to wildlife. Deer eat the fruits and foliage, while cottontail rabbits will feed on the twigs and bark. When food is scarce in winter, the berries are a good food source for birds.   

  • Some simple beneficial tips:
    1. If you think you’ve come into contact with any of these poisonous plants, wash with a grease-cutting dish soap to break down oils asap. Some websites suggest washing within a half hour or even up to an hour, though my personal physician recommends within 10 minutes.
    2. Regularly wash sporting equipment and garden tools. 
    3. Remember the saying, “Leaves of three, let them be!” to help avoid the plants. 

Jill K. McDonald is a freelance nature & travel educator, writer, photographer, and speaker. She can be reached by email at or connect with her on Facebook at:

%d bloggers like this: