POISON IVY, Rhus radicans L. 1, root and base of plant; 2, flowering branch; 3, cluster of berries, and single berry; 4, flower. Woody perennial, reproducing by seed and rootstocks. The plant may be either a low shrub or a vine climbing high into trees. In climbing it is supported by aerial roots along the stem. Leaves consist of 3 large shiny leaflets each 2 to 4 inches (5 to 10 cm) long, pointed at tip. Leaflet edges either smooth or irregularly toothed. Flowers small, green, 5-petaled, borne in a head 1 to 3 inches (2.5 to 7.5 cm) long. Berries small, white, round, and hard. Found in open woods, fence rows, thickets, orchards, and wasteland. All parts of this plant contain a poisonous material which may cause blistering of the skin. The plant changes from a bright green to a very attractive red or reddish-yellow in the fall, tempting unwary collectors. This is a variable species, not only in habit of growth, but in leaflet shape, rooting habit, pubescence on leaves, petioles, and fruit.