Poison sumac is a plant often misunderstood, particularly regarding its growth habit. Many are unsure if it grows as a vine, leading to confusion. Understanding its true appearance and growth pattern is important for accurate identification, helping individuals recognize the plant and avoid contact.
Understanding Poison Sumac’s Growth
Poison sumac is not a vine; it grows as a woody shrub or small tree. It typically reaches heights between 5 and 25 feet, sometimes up to 30 feet, developing an open crown and often sprouting multiple stems from its base.
It thrives exclusively in very wet environments, such as bogs, marshes, swamps, and along riverbanks. It prefers acidic soils and is often found with its roots in standing water or saturated ground. Its natural range spans the eastern United States and parts of eastern Canada.
Key Identification Marks
Poison sumac leaves are compound, with multiple leaflets attached to a single stem. Each leaf typically has 7 to 15 leaflets, which are oval to oblong with pointed tips and smooth, untoothed edges.
Young leaves often emerge bright orange, maturing to a dark, glossy green on the upper surface and paler green underneath. In the fall, the foliage transforms into a red-orange color. The stems and leaf stalks are frequently reddish.
The berries are small, waxy, and typically grayish-white to yellowish-white. Unlike other sumacs, these berries hang downwards in loose clusters from the leaf axils. The bark is generally smooth and ranges from light gray to grayish-brown, darkening as the plant ages.
Poison Sumac vs. Poison Ivy and Oak
Poison sumac stands apart from poison ivy and poison oak primarily in its growth form. In contrast, poison ivy frequently grows as a climbing vine, though it can also appear as a low-growing shrub. Poison oak typically forms a shrub, but can also grow as a vine.
A visual distinction lies in their leaf structures. Poison ivy and poison oak are characterized by their “leaves of three” leaflet arrangement. Poison ivy leaflets often have a more pointed shape, while poison oak leaflets are typically more rounded or lobed.
Differences in berries also aid in identification. Non-poisonous sumacs, by comparison, have red berries that stand upright. Poison ivy and poison oak also bear white or translucent berries, sometimes yellowish-white for oak varieties. Poison sumac is found exclusively in wet, swampy habitats, while poison ivy and oak can grow in a wider range of environments, including drier wooded areas.