Living with European Buckthorn
As I get the opportunity to pass by or go through the gardens of others, I often see trees that give me the willies. These trees are the European Buckthorn. In stands of one or two young trees or shrubs, they look harmless and almost handsome with their strong, clean foliage and dark berries. Unfortunately, the unsuspecting homeowner who leaves these visitors from the underworld to their own devices is in for a major battle.
The European Buckthorn was brought here by the early settlers for hedges and is both drought and shade tolerant. It is listed in Ontario's Weeds Act as a noxious weed, with Peterborough and the surrounding area having a serious infestation. It can be recognized by its dark glossy, finely toothed, deeply veined, oval leaves. It has shiny black berries and the larger branches often have a single thorn at the tip.
Buckthorn grows rapidly from the berries and from cut stumps. Not only does each berry have several seeds, but also the fruit causes a severe laxative effect in birds, quickly distributing the seeds. Some seeds also go to your neighbour's yards where these devious plants can sneak up on someone else. Then later, after you have almost won the battle, the birds bring them back from next door. The trees will get to be very large shrubs with several, four to six inch trunks blocking out the sun and releasing poison into the surrounding soil so that no other plant can grow. Buckthorn is happy to grow tangled in the base of other shrubs or trees and they will form very dense stands with in a few years. In short, they will take over if you let them, so don't.
Since moving to our present home in Peterborough in 2000, much of our gardening energy has been devoted to battling Buckthorn. The first year we tried grinding the trees to mulch but subsequently found that the mulch seemed to inhibit the growth of other plants. The larger wood is not clean burning in the fireplace, but I have read that the unusual yellow-orange wood is useful for woodworking. If you only have a few seedlings, you can pull them out, but if your property has been left as long as ours was, you will have to get out the saws. A strong solution of a glyphosate weed killer (50:50) applied immediately to the cut stump may help. We have found that if you get the entire stem out at the base of the tree, it does not seem to come back from the roots, but you have to keep up continued vigilance on the seedlings. There are male and female trees, so if you need to prioritize, you can take out the females first.
If you do not have European Buckthorn yet, please keep an eye out for it; if you have a few, pull them out; and if your property is infested as ours was, may the Force be with you.