Poison Ivy in Summer photo by Lisa Bird

Poison Ivy

Toxicodendron rydbergii

Appearance: Poison Ivy is a member of the Sumac family and recognizable by its three shiny leaflets, white flowers in March to June, and smooth white berries later in the summer.  It grows to a mature height of 2 feet.

Habitat: Found in the plains and foothills, it grows on rocky slopes and at cliff bases in full sun to partial shade.

Landscape suitability: Poison Ivy contains a milky oil which can cause skin rash, sometimes severe, in humans.  Livestock and wildlife, however, can browse it without any ill effects.  Interestingly, Poison Ivy is in the same plant family as some of our most delicious fruits and nuts like cashews, pistachios, and mangos.

Poison Ivy in Fall photo by Lisa Bird

Contributed by Susan Thomas, Colorado Native Plant Master

Sources:  Native Plant Master Manual, El Paso County; Colorado State University; 2008

Colorado Flora, Eastern Slope; William A. Weber and Ronald C. Wittmann;    University Press of Colorado, Niwot, Colorado; 1996