Pruning trees–especially apple trees–is recommended between January and March each year to avoid potential disease and insect problems during the summer months. This winter period is also an excellent time to control unwanted or invasive woody trees and shrubs such as buckthorn, Siberian elm, Japanese barberry, and oriental bittersweet.
Pruning Apple Trees
For pruning apple trees, you want to prune the tree to have well-spaced branches and a balanced appearance, while eliminating problematic branches (those that are broken, diseased, or dead).
General pruning guidelines include:
- Remove diseased, broken, or dead branches
- Remove any downward-growing branches
- If two limbs are crossed, entangled, or otherwise competing, remove one of them completely at its base
- Remove any limb along the trunk that is getting bigger in diameter than the trunk
- Remove suckers coming up from the roots or low on the trunk
- Remove watersprouts, which are vigorous vertical branches
- Make pruning cuts close to the branch collar at the base of the limb; for larger limbs, start the cut from the underside of the limb to avoid tearing the bark
- Remove large limbs first, starting with the top of the tree.
Information on pruning apple trees and general pruning tips are available at these sites:
Growing apples in the home garden
Pruning trees and shrubs
US Forest Service: How to prune trees
Pruning: What, Why, When, and How
Buckthorn and Woody Plant Control
The procedure for woody plant control is to positively identify the tree or woody plant to control, cut the stump, and treat the stump with herbicide and dispose of the brush. Winter woody tree identification is important because deciduous trees have no leaves. Buckthorn usually has a tiny thorn at the very tip of most branches. Other desirable trees have a bud. Buckthorn has male and female trees. Female trees have purplish-black berries and should be selected to control first to prevent spread. The most effective brush killers for cut stump treatments include Triclopyr as one of the active ingredients. For winter treatments an oil base and ester formulation is best. Follow label directions. Herbicide treatments are less effective when the sap is flowing.
Cut the tree trunk an inch above the ground and treat the entire bark or cambium layer (outer rim, edges of the stump). If any part of the exposed bark layer is not treated, the tree may resprout. Rope or flag a small plot to facilitate systematic treatment. Monitor treated sites seasonally.