Identifying Poisonous Plants

Plant Identification

How can you identify poisonous plants?

The old saying “Leaves of three, let it be!” is a helpful reminder for identifying poison ivy and oak. However, it does not apply to poison sumac, which usually has clusters of 7–13 leaves. Even poison ivy and poison oak may have more than three leaves. Their form may also vary greatly depending upon the species, the local environment, and the season.

You can avoid exposures to poisonous plants if you:

• Know what they look like throughout the seasons.
• Can tell them apart from their common lookalikes that are not poisonous in the local area.

Poison Ivy

Photos courtesy of U.S. Department of Agriculture

• Eastern poison ivy is typically a hairy, ropelike vine with three shiny green leaves budding from one small stem. The leaves may be red in the fall.
• Western poison ivy is typically a low shrub with three leaves that does not form a climbing vine.
• It may have yellow or green flowers and white to green-yellow or amber berries.

Poison Oak

Photos courtesy of U.S. Department of Agriculture

• It is typically, a shrub with leaves of three, like poison ivy.
• Pacific poison oak may be vine-like.
• It may have yellow or green flowers and clusters of green-yellow or white berries.

Poison Sumac

Photos courtesy of U.S. Department of Agriculture

• It is a woody shrub that has stems with 7–13 leaves arranged in pairs.
• It may have glossy, pale yellow, or cream-colored berries.