Look for three small leaflets. The leaf itself is made- p of these leaflets with the tallest one in the middle. This will be the same on a shrub or vine.
Look out for a small shrub In the West, but note that poison oak also might grow as a vine in that area. In the East, poison oak only grows as a shrub and has the three leaflets to form its leaves.
Check for yellow or green flowers and clusters of green-yellow or white berries as another identifying factor. These will not always be present, but if you notice them on a plant with three leaves, there is a good possibility the plant is poison oak, according to the Centers for Disease Control and Prevention (CDC).
Identify poison sumac by its leaf structure. Poison sumac has several rows of paired leaflets and has one additional leaflet at the end, says the American Academy of Dermatology (AAD). Usually there are seven to 13 leaves on a stalk.
Look for spots on the leaves of the poison sumac. The spots will look like blotches of black enamel paint and contain urushiol, which is the oil that causes the rash after coming into contact with your skin, says the AAD.
Keep an eye out for poison sumac in the standing water of bogs in the Northeast and Midwest. In the Southeast, look for poison sumac in swampy areas.
Identify poison ivy as a plant with three leaflets on each stem whether growing as a shrub or ivy in any area of the country. Appearing differently depending on the area of the country is a poison ivy trait.
Avoid vines that grow up trees and poles in the eastern United States. Poison ivy appears as a hairy, rope-like vine with three shiny green leaves---sometimes red in the fall---on one small stem.
Look for poison ivy to resemble a small shrub in the West instead of a climbing vine. The shrub version also has three shiny green leaves budding from one small stem.
Observe yellow or green flowers and light green or white berries that can occur on both the Eastern and Western varieties of poison ivy. When poison ivy berries ripen in late summer to early fall, they turn from a pale green to a whitish color.