When pruning trees and shrubs, should I make the cuts level or at an angle?
Answer: It depends on the desired result of the cut. There are two kinds of pruning cuts when you're dealing with live wood: a heading cut and a thinning cut.
A heading cut prompts new growth from the buds closest to the cut (just behind it). Heading cuts should be used carefully, with the goal of reducing the plant's height and keeping its natural form. A heading cut should be made about a quarter-inch above a bud and it should point toward the bud. (The length of stem from bud to cut should be shortest on the bud side of the stem.)
A thinning cut is used to reduce the overall density of a shrub. Thinning cuts are made where the stem is attached to another stem or the trunk. It should be made just above the parent stem or just above side branches on the parent stem, and should point away from the next lowest bud.
For more information and illustrations of thinning and heading cuts, see "A Guide to Successful Pruning" by Virginia Tech Cooperative Extension.
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