Buckthorn
Buckthorn: What You Should Know. What You Can Do. [PDF]

Buckthorn Video Series
Common buckthorn (Rhamnus cathartica):

Common buckthorn leaves. Photo: Erin O'Connell
https://www.dnr.state.mn.us/invasives/terrestrialplants/woody/commonbuckthorn.html
Glossy buckthorn (Frangula alnus):

Glossy buckthorn. Photo: Minnesota Department of Agriculture