How Not to Prune a Tree
When I moved to Tennessee I was appalled to see the way trees are pruned here, especially the practice called topping. In yard after yard I saw trees with their crowns lopped off, leaving ugly stubs.
These trees are pruned to reduce their height, perhaps because the tree is starting to tower over the house. Or its branches block sunlight. Or the branches are too near to utility lines. When I asked why the trees were pruned in such an ugly manner, I was told time and again that this is how trees are supposed to be pruned.
I would see tree service trucks with signs proclaiming “tree surgeon.” More like tree butchers, I thought. Still, I started to wonder if everything I believed I knew about tree pruning was wrong. After all, how could all those good people be so wrong?
As it turns out, my instinct was right. Soon after I discovered this abominable tree pruning method, Plantamnesty was organized with the mission to “end the senseless torture and mutilation of trees and shrubs.” Uninformed tree trimmers mistakenly believe topping reduces the storm hazard of falling branches, when actually topping increases the hazard of falling branches and even downed trees.
Topping hurts trees, and is now illegal in many communities. It makes a tree dangerous because it encourages rot, weakens the tree, and makes it more vulnerable to wind breakage and storm blow-down.
Even when branches are removed from a tree that hasn’t been topped, I see the branches lopped off in mid limb, leaving stubs. That offends me no end. Not only is it ugly, it’s bad for the tree.
Here’s the right way to prune: If you look closely at a branch coming out from the trunk of a tree, you will see a swollen area on the trunk, surrounding the branch. The swollen ring is the branch collar. Its job is to fill in and seal the wound left if the branch is removed.
When a branch is trimmed to a stub, the collar can’t seal the wound. The stub will die back, and the dead wood will attract insects, rot, and infection. Sometimes the infestation gets bad enough to push past the branch collar’s protection and into the trunk of the tree itself. Not good!
The proper way to prune a limb is to cut close to the branch collar, without cutting into the collar. Then the branch collar can get to work doing its job of healing the scar. Instead of being topped and lopped, a tree deserves the dignity of being properly pruned.