Buckthorn trees, although sometimes attractive, are considered invasive and are able to crowd out other plants. They grow quickly and in thick groves with low-hanging branches, crowding out native plants and providing habitat for only certain species of birds and forest animals. State and local governments spend large amounts of taxpayer funds each year to try and eradicate buckthorn trees from nature preserves, parks and other wildland areas. Removal of the trees from private property can help reduce this problem as well as keep them from taking over yards and fields.
Cut down large buckthorn trees with a chain saw or handsaw. Large trees are those with a diameter of three inches or more.
Pull small buckthorn trees out of the ground by hand. You can use a hoe on very small trees or simply grasp saplings while wearing gardening gloves and pull them out, root and all.
Spray the stumps of the larger trees with herbicide, covering them thoroughly, while wearing rubber gloves for protection. The Minnesota Department of Natural Resources recommends glyphosate, which is found in products such as Roundup, or triclopyr, which is found in herbicides such as Brush-B-Gon.
Wait several days or up to two weeks for the herbicide to take complete effect.
Dig out the stumps, removing as many roots as possible along with the stumps.