DNR Question a Da Week

[Lee Borgersen]

         DNR Question Of The Week

10/22/15

Q: I?ve heard that fall is a good time to remove buckthorn on my land. What?s the best way to try and control buckthorn?

A: There are two types of invasive buckthorn in Minnesota. Common buckthorn is easily found in late fall when many native shrubs and trees have lost their leaves. Common buckthorn will often have green leaves through November. Glossy buckthorn does not stay green as late as common buckthorn. Use caution as many native trees look similar to buckthorn, and some native trees hold their leaves into the winter. Before you cut, make sure you know you are cutting buckthorn and not a native tree.

Buckthorn plants two inches in diameter or larger can be controlled by cutting the stem at the soil surface and then treating the stump with herbicide or covering the stump to prevent re-sprouting. This can be effectively done with hand tools, chain saws or brush cutters. Stumps should be treated immediately after cutting (within two hours) with an herbicide containing triclopyr (many brush killers, Garlon 3A or 4) or glyphosate (Roundup and others) to prevent re-sprouting. An alternative if only cutting a few stumps is to cover them with a tin can or black plastic to prevent re-sprouting. For smaller plants, pulling or applying herbicide are good options for control.

Laura Van Riper, DNR terrestrial invasive species coordinator