Tree pruning, a near-surgical operation to reduce or shape a tree

Need to prune a tree, whether due to a dead branch, a hazard, or simply an eyesore? Not sure how to go about it?Follow our advice to know when and how to prune, while minimizing risk to both you and your tree.

When to prune a tree?

Best time for pruning is in April, May, and June. During these months, photosynthesis kicks off, sap surge is over and wounds heal faster. You might consider pruning in winter, but only when Jack Frost isn’t in town. In any case, you should not prune:

• In early spring, as plants unfurl their first leaves to start photosynthesis. Pruning at this time will weaken them.
• Right before leaf fall, as plants are transferring nourishing substances from leaf to trunk to generate new leaves come spring.

For the tree itself, it will always be better to undergo pruning early on, when undesired branches are still small. Envision your tree growing and decide which shape it should have. Ideally, you’d prune away excess branches every 2 years, keeping only the final structural branches. This guarantees that you only ever need to cut small branches instead of riskier large ones.

How to prune a tree?

Which tool to choose?

Branch size guides your choice. Use a pruner or a lopper for small diameters. You’ll also see these in stores as pruning shears or branch cutters. For bigger diameters, greater than 1 or 1½ inches (3 or 4 cm), a pruning saw makes cleaner cuts. For really big branches, you might need a chainsaw.

How to go about it?

Before you start pruning, make sure your tool cuts well. If it’s a pruner or lopper, it needs to be sharp enough. For a saw, make sure it doesn’t lack any teeth, or you’ll end up tearing instead of sawing. For a chainsaw, check that the chain is sharp before you start. Then, to prevent infection or disease spread, clean and sterilize your tools after each cut.

• Where to cut?

Allow your tree to heal by not cutting too close to trunk. Cut angle should be perpendicular to the cut branch axis (not parallel to trunk).

• Cutting technique

For smaller diameter branches, with a pruner or a lopper, no special technique. Respect pruning area and cut crisply and cleanly.

Things get trickier when you have to use a saw for a larger branch. You’ll need to follow three steps:

1. Step 1: Make an incision a few inches (a few centimeters) under the branch. This stops any tearing when you make the step 2 cut.
2. Step 2: Move a few more inches (a few centimeters) away from the trunk and step 1 incision, then cut branch completely, starting from the top.
3. Step 3: Move closer to the trunk and make the final cut, not compromising the healing area.

Safety rules

Beyond recommended protective gear (gloves, glasses…), you must be mindful of your work area. If it’s at human height, no special precautions necessary. But, if you need to prune much higher branches, use a pole pruner or a pole saw and secure your surroundings so nobody can enter.

Don’t work on a ladder, stepladder or any other unstable situations. Of course, for your safety, in case of a larger and more technical project, better call a professional.

Disposing of waste

It’s important to schedule this step as well, since piles of leaves and wood can attract undesirable animals like snakes or rodents. Best is to immediately shred branches into rich ramial chipped wood, but you might want to keep a small pile as shelter for beneficial animals like the hedgehog and shrew.