Twigs are often tipped with a spine. Leaves and bud scars are nearly opposite to opposite. 3-4 seeds are typical. Leaves are broadly elliptic, rounded to pointed at the tip, and toothed. Both upper and lower leaf surfaces are smooth.
Leaves stay green late into fall.
Two native species of buckthorn are found in Missouri. Carolina buckthorn is essentially restricted to the Ozark region in Missouri, whereas lance-leaved buckthorn is found throughout the state with the exception of the Mississippi Lowlands of southeast Missouri. Both species grow in soils derived from limestone or dolomite. Common buckthorn can be distinguished from both native species by its opposite or near opposite leaf arrangement and by the presence of spiny tips on its twigs. Its leaves are abruptly pointed to rounded at the tip, whereas the two native species both have leaves that are more gradually tapered to a point at the tip.