What does a buckthorn look like?

Buckthorn is a deciduous shrub or small tree that typically grows between 3 to 20 feet tall. It features slender, spiny branches and glossy, dark green leaves that are oval-shaped and can be up to 3 inches long. In the fall, its leaves turn yellow to purple, and it produces small, round berries that are usually black or dark purple. The bark is grayish-brown and often has a distinctive, rough texture.