Woodland Invasives

Common Buckthorn (Rhamnus cathartica)

Common buckthorn is an understory shrub that can reach heights of 20 feet. The shrub often is multi-stemmed with irregular spreading branches. Flowers are small, inconspicuous, green, and clustered near the leaf axils. Dark black to purple berries are in loose clusters around leaf axils and ripen in late summer and usually persist until winter. The bark of common buckthorn is a rough-textured grayish brown. When cut into, the pith of buckthorn is an orange color. Leaves are finely toothed, dark green, and oval-shaped. The leaves have broadly arcing veins and often have a folded appearance at the tip of the leaf. Leaves are usually opposite, attached to the stem adjacent to another leaf. Stems usually have a sharp point at the terminal end.

Major characteristics

Sharp point at end of stem
Dark green, finely toothed leaves
Leaves opposite (usually)
Arcing veins of leaves
Black-purple berries or small green flowers from leaf axils

Other web-sites about Common Buckthorn identification:

http://www.nps.gov/plants/alien/fact/rhca1.htm
http://tncweeds.ucdavis.edu/esadocs/franalnu.html
http://www.dnr.state.wi.us/org/land/er/invasive/factsheets/buckthorns.htm