Tree trimming tips

Basic pruning rules on when to trim trees and how to trim trees
Trimming trees at the right time

You may have heard the old saying about tree trimming that goes something like this: “Trim trees anytime your saw is sharp.”  This may be true when it comes to removing broken and dead branches, but in many cases, the correct timing is very important.

Weeping cherries should be trimmed within 30-days after they bloom
Weeping cherries should be trimmed within 30-days after they bloom
Trimming flowering trees: “Timing, timing, timing!”

Most flowering trees set their blossoms the year before they bloom. Therefore, they won’t bloom if these flower buds are trimmed off the tree. The best rule is to always trim flowering trees within 3 weeks of when they finish blooming. That should prevent you from inadvertently removing buds containing next year’s flower show.

Trees that shouldn’t be pruned at certain times of the year:

OAKS – Oaks should be not be trimmed from April thru October, due to the prevalence of Oak Wilt disease pathogens during that time frame.

DOGWOODS – If you trim Dogwoods in April or May, it will make them more susceptible to the dogwood borer. This insect severely damages the vascular system of the tree after boring into the trunk.

MAPLES – Maples trimmed at certain times of the year will “bleed” or drip from the pruning cuts. Bleeding is most likely to occur when Maples are pruned in the seasons just before and right after winter. Studies indicate that “bleeding” doesn’t hurt the tree, so it becomes more of a cosmetic issue. If you want to prune Maples without bleeding, it must be pruned when it is fully dormant in the middle of winter, or during late spring or summer when it’s in full leaf.

Photo above and below:
Severely cutting back major branches causes weak growth in the form of multiple branches that grow straight up, ruining the natural structure of the tree. These fast growing shoots are known as “water sprouts.”

‘Topping’ Silver Maples

AVOID Topping: Our number one choice of trees not to plant is Silver Maple (Acer saccharinum). Their rapid growth may be desirable to some for the first 20 years, but after that most homeowners are forced to make a decision; trim-it or remove-it. Unfortunately, the decision is usually to trim-it using a method known as “topping.”

Topping creates a “hat rack” appearance and forever ruins the branching structure of the tree. A profusion of weak growth known as “water sprouts” is created at each cut. Where there was once a well-formed branch, there are soon 5 or 10 sprouts that grow straight up, faster than ever. Homeowners are then forced into the vicious cycle of topping the tree again, every few years. BOBSCAPING SOLUTION: Remove overgrown silver maple trees and plant a more desirable tree species.

Water sprouts erupting from a topped Silver Maple tree
Water sprouts erupting from a topped Silver Maple tree
Trimming trees in the right place

One of the biggest pruning mistakes is cutting off branches in the wrong place. Amateurs tend to leave too much of a stub when removing branches. Once the stub dies off, it creates an entry point for disease pathogens and destructive insects.

Unlike human beings, trees don’t regenerate tissue. While our skin replaces itself, trees grow new tissue around wounds and compartmentalizes them with callus tissue. Once a a tree compartmentalizes an old wound, it has a much better chance of survival.


Efforts should also be made not to wound tree trunks with lawnmowers, tractors and other machines. Trunk wounds create opportunities for destructive fungi.

A natural defense system is built into trees, in the swollen area at the base of branches, known as the “collar” — right where the trunk intersects the branch. Flush cuts are important to make, provided you don’t remove the collar. Proper pruning cuts should be made just beyond the collar, without leaving a stub, but still leaving the swollen area.

Removing a tree branch
Steps for sawing-off a tree branch:
  1. About one or two feet from the trunk, make an undercut one-third of the way up through the bottom of the branch. Your saw will get pinched if you cut too far up.
  2. Make your second cut completely through the branch from the top side, about three inches out the branch from your first.
  3. This should allow the branch to fall away without tearing the branch bark into the trunk.
  4. Keep it Safe – Never do tree trimming or removal work that should be done by a professional. Heavy tree branches can seriously injure you in a split-second!
More safety tips when trimming trees:

Never stand on a ladder trimming trees. This is just asking to get hurt!

Tie into the tree in 2 places, using professional grade equipment and techniques: 1) Use a safety line through a strong crotch in the top of the tree, and 2) Use the strap on your tree climbing saddle to tie-in.

Be sure to properly “notch” a tree trunk when you are felling it. Kickback can kill you!

Take a class in chain saw safety and operation. Wear safety chaps lined with material that will protect your legs.

Eye protection and a hardhat should be worn (also wear ear protection).

False economy — Hire a professional for jobs you can’t handle — it’s really not worth getting seriously hurt, or damaging expensive property, just to “save money.”


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