Poison Ivy

Scientific Name: Toxicodendron radicans

Category: plant

Poison Ivy

Brief Description

A woody vine or shrub known for causing allergic skin rashes in humans due to urushiol oil.

Characteristics

Compound leaves made up of three leaflets ("leaves of three, let them be"), alternate leaf arrangement, variable margin shapes (toothed, lobed, or smooth), and greenish-white flowers followed by grayish-white berries.

Habitat

Found in wooded areas, forest edges, fields, roadsides, and suburban yards.

When to Find It

Active growth and most hazardous from spring through autumn; loses leaves in winter.

Conservation Status

N/A

Ecological Role

Provides food and cover for birds and other wildlife, which eat the berries and disperse seeds.

Easily Confused With

Boxelder (Acer negundo) seedlings, which also have three leaflets; distinguish by boxelder's opposite leaf arrangement versus poison ivy's alternate arrangement.

Observation Tips

Do not touch or brush against the foliage. Wear long sleeves and pants if working near suspected areas.

Interesting Facts

Urushiol, the plant's irritating oil, remains active on surfaces (including clothing and pet fur) for years if not washed off properly.