What is buckthorn?
Common buckthorn was first brought to Minnesota from Europe in the mid-1800s as a very popular hedging material. Shortly after its introduction here, it was found to be quite invasive in natural areas and in the 1930's the nursery industry stopped selling it. However, many buckthorn hedges may still be found in older neighborhoods throughout Minnesota. European or common buckthorn and glossy or alder buckthorn are listed as restricted noxious weeds in Minnesota, meaning it is illegal to import, sell, or transport buckthorn in Minnesota.
Why is buckthorn such a problem?
Buckthorn is a non-native shrub or small tree that crowds out native plants for nutrients, light, and water. It degrades wildlife habitat and diversity, smothers native plants by forming a thick layer of vegetation, and is easily spread by birds which ingest the berries. Since Buckthorn has no natural disease or insect predator it is very difficult to keep its population under control.
Do I have buckthorn in my backyard?
Buckhorn is pretty easy to identify. It leafs out earlier in the spring and keeps its leaves much later in the fall than other trees and shrubs. Buckthorn leaves are egg-shaped, glossy, and finely toothed on the edges. The fruit is round, berry-like and formed in clusters. The bark of buckthorn trees is gray in color. Older trees or larger branches have flakey bark while younger trees or smaller branches have smooth bark with raised white bumps. Look for yellow sapwood under the bark.
What can I do to control buckthorn?
Removal of buckthorn can be an overwhelming process and can depend on the size of the plants.
- Seedlings can be hand-pulled or removed with a hoe or puller.
- Pull up small tress (less than 1") by hand.
- Loppers work great for small or medium sized shrubs.
- Larger trees can be cut with a saw. Handsaws work well, but a chainsaw is more efficient if you have a lot of buckthorn.
- Dispose of brush properly and be very careful if there are berries on the branches. There are several seeds in every berry, and the seeds can persist in the soil for years before growing.
- Dig out stumps with a shovel or grub axe or treat the freshly cut stumps with an herbicide such as Round-Up.
Buckthorn can be difficult to control. Other helpful tips include:
- Remove trees with fruit first. This will reduce the amount of seeds added to your soil each year.
- Annually pull or cut small seedlings. Buckthorn is a lot easier to control in early stages.
- When removing buckthorn, replace with native shrubs to help discourage encroaching buckthorn.
For more information about buckthorn and how to manage it, go to MN DNR.