1. Rip it out by the roots.
If you have a few buckthorn bushes, but not acres worth, one option is to pull them out by their roots with a simple chain or a Brush Grubber and your truck or a heavy-duty tractor. This option has the benefit of removing the bush by the roots, so there’s no chance of it regrowing.
2. Mow it down.
While a regular lawn mower is no match for buckthorn, a heavy-duty brush cutter such as the DR Field and Brush Mower is. Any bushes or clumps of bushes up to 3″ in diameter can be easily mowed down with a DR and chopped into a fine mulch. This is a fast and relatively simple solution. We recommend treating the remaining stumps with herbicide after mowing so that they don’t regrow.
3. Poison the bark.
This technique is known as basal bark treatment. Treat the bottom 12-18 inches of each buckthorn shrub with a Triclopyr ester-based chemical herbicide. The plant will eventually die, and you can remove the dead remains either by mowing them over with your brush mower, or by pulling them out by their roots, depending on their size.
4. Pull the little ones out by hand.
To prevent little seedling buckthorns from growing into full-fledged shrubs that will crowd out other plants, pull them out by hand when they’re small enough to do so. Be sure to dispose of them in such a way that the seeds don’t spread even further.