Disclaimer: The best advice we can give is to call a professional — for your own safety, for the safety of others and for the health of your tree. Every year homeowners and professionals are hurt and killed doing this work because it can be very dangerous.
How to Prune a Tree: DIY Tree Trimming Tips
DIY tree trimming gets us a lot of work, usually when the client has cut partway through the tree and realized they’ve made a mistake. Sometimes it’s just the realization that cleaning up an entire tree is a lot of work or takes a lot of time. We provide tree pruning as a service for a number if clients in this category. Sometimes DIY tree cutting is a budget issue that can be addressed by understanding the costs of tree work and reducing the price.
Other times, it’s totally fine for anyone to prune their tree. The tree might be very small, the branch you want to cut is small and easy to reach, or perhaps you’ve got some experience. We don’t believe in holding back information. Sometimes it makes sense to hire an arborist, and sometimes it doesn’t.
If you’re absolutely certain that your DIY tree trimming project is small enough and safe enough for you to handle, there are some things you should know.
1. Does Proper Pruning Damage Trees?
Pruning is an effective way to keep trees healthy, safe and beautiful. When done by a qualified arborist, it will not damage the tree, but if you jump in to cut the tree yourself you definitely have a good chance of damaging it or yourself. There are many, many guidelines and best practices to proper tree pruning — too many to summarize in a basic blog post.
The biggest things to keep in mind if you’re wondering how to trim a tree are:
- Don’t take too much
- Anything you do is permanent
- Trees cannot heal themselves
- Make proper cuts
Don’t Take Too Much Off
If you cut too much off, cut off something important (like the top of the tree), or make a bad cut that rips the bark, you will damage the tree in ways that can’t be fixed. We can’t glue a tree back together, or make it regrow something that has been cut off or damaged. When you cut a tree branch or a tree itself, you need to leave enough on it (like leaves and greenery) for it to survive, or else the entire thing will die back. When pruning, you want to only remove about 10-20% max of the branch or tree to ensure it survives.
Start by cutting off a small amount. Cut a little bit, then a little bit more. You’d be surprised what a difference it can make. Step back and assess your work as you go.
We often get asked to prune branches away from a house or patio to increase sunlight or stop branches from rubbing on furniture or shingles. When we do this, it is called “clearance pruning” or “elevation.” Clearance pruning provides a set amount of space horizontally between the tree branches and the house or object. Elevation pruning lifts the canopy up to make it higher — let’s say we want branches to be 4ft higher that where they are. How would you do this?
Option 1: Prune the branches 4ft from the end. This may work, but it may also result in an even greater gap, or not enough green on the branch for it to survive.
Option 2: Prune 1ft off the end to see how much it lifts up, and repeat as necessary until the branch is the required distance away. Most tree branches will start to lift once you take a bit of weight off the end, as they are simple levers. Imagine a seesaw: You only need to take a little bit of weight off one end for the other side to start rising. Keep taking little bits off until you achieve the height you want.
Trees Don’t Heal, They Seal — Sometimes
Unlike humans and animals, when a tree is wounded, it will not heal. If you cut you arm, a scab will form and new skin — scar tissue — will eventually replace the old. Trees grow around the wound, but it is never “gone.” The bark simply grows over top of it. The original injury remains and is a source of weakness. If the wound is too big, it will never be covered. This process of sealing wounds is called compartmentalization. Some trees are good “compartmentalizers,” while others are very bad at it.
Let’s put it another way. You can think of pruning as what you’re taking away from the tree (branches, limbs, stems), but you should also think of what you are placing in the tree: defects (weak points) and rot. Since these will never heal and can create long term problems, it is important to think through your pruning cuts.
That’s also why it’s important to understand some basic tree biology and have a plan before you begin you DIY tree trimming. Here are some great places to learn about trees and what proper pruning or trimming involves:
- Pruning Handbook from Purdue University
- New Mexico State University Tree Pruning Guide
- Fiskars Tree Trimming Guide
Make Proper Pruning Cuts
Think you should take a saw and start cutting through a branch? Wrong!
Arborists use a technique called the “three cut method”, or a “snap cut.” This method gives a greater amount of control, and can help prevent damage from the pruning.
The three cut method involves a style of cutting known as “bypass.” A bypass cut is where you cut through 60-80% of the tree branch on one side, and then make a parallel cut 3-6 inches away on the other side that is also 60-80%.
To do this properly, you want to make your first cut on the side where the tree branch is going to fall. If the branch growing parallel to the ground, this cut will be on the bottom. Then, you want to do the top cut. When you’re making the top cut, the branch may snap off. If it doesn’t, keep cutting. After the branch is separated, cut the remaining stub off. You want to cut the stub close to the tree, but not so close as to damage the “branch bark collar,” a ridged section of growth around the base of the branch that attaches it to the tree.
You can also make this cut more controlled by doing it from the side rather than from the top and bottom. If the branch is not too heavy on the end and you don’t cut too far through, making a sideways bypass cut will mean that the branch won’t break off on your second cut. This allows you to put down your pruning saw to grip the branch with both hands and snap it off.
There are many, many other styles of cuts for pruning a tree and the way that different species will react to different things can change the type of cut you’re making. Sometimes you may want to use a notch to make the tree branch move in a certain direction. This is an example of some of the training that professional arborists receive.
2. What Is the Best Time of Year to Prune?
Many trees can be pruned year round, and Vista Tree works through the winter on tree pruning and removal. Oak trees in Toronto are one species that should only be pruned in off seasons, due to the threat of oak wilt and becoming infected. Oak wilt is devastating oaks in the USA, and it is on its way here. Pruning in the winter keeps oak trees safer from this disease.
If you’re doing DIY tree trimming, you’re probably safer to do your pruning in the spring or summer to avoid icy and cold conditions. If you’re thinking of pruning an oak tree, however, you should either wait or call a professional. Research the tree you’re planning on trimming before you cut to see if there are any pests or diseases that it may be vulnerable to if you start cutting.
3. Can Trees Be Killed by Too Much Pruning?
Yes. Yes. Yes. Properly done, pruning a tree in an urban or city environment is really important. Trees in a city get extra light, too little water, too much pollution and too few nutrients. What goes into the tree from the environment comes out of the tree in how big, healthy, safe and beautiful it is — just like us. A terrible diet won’t help anyone feel or look better, and the same is true for trees.
When trimming a tree, removing too much from the tree will cause many problems. Every twig, every branch, every limb, every stem contributes to the overall tree. Each section of the tree takes care of itself, and then contributes some back to the whole of the tree — similar to taxes!
When too much is removed, the tree experiences a sudden decline in the available energy all over and also has to spend energy sealing over the pruning wounds. At the same time, rot, pests or diseases can be introduced causing more problems. All of these factors stress a tree and can lead to decline or death. Removing too much from tree or branch can cause serious problems for the remaining branches and limbs as their supply of energy is reduced.
When Is It Too Much?
There is a tipping point — after you cut too much off a tree, it cannot recover from the injuries and the lost energy from the leaves and branches you cut off.
If you’re going to trim your own small tree, start very small and make a few well-selected cuts.
There are many DIY tree pruning options for homeowners, but if in doubt you should likely get an opinion at least. Pro tip: Tree companies in Toronto offer free estimates. Call to get one and ask some questions about anything you are in doubt about. The advice will be free and educational if you call a professional company. You don’t have to accept a quote, but it will give you more information about how to DIY.
And if you decide it’s too time consuming, hard, dangerous or whatever for you to do, you’ll already understand the budget you need to be working with to have a pro arborist do it.
4. What Equipment Do I Need?
You’ll absolutely need:
- A first aid kit
- Safety glasses — really
- Cut-resistant gloves like Showa latex dip
- A small greenwood handsaw like a Silky Zubat or similar smaller handsaws (you can buy these from places like The Arborist Store, Maple Leaf Ropes, or Lee Valley Tools — general hardware stores like Home Depot may carry some)
You may need, and we strongly recommend:
- Hard hat: Being hit in the head with wood is one of the leading causes of serious injury
- Safety boots / steel or composite toe work boots: Gravity, weight and toes are a bad combo
- Chainsaw pants or chaps if you’re using a chainsaw
- Hedge trimmer, if hedging
- Pole pruner, if pruning a tree or hedge
- Pole saw, if pruning a tree
Safety Glasses, Really
People greatly underestimate the weight of wood, especially with leaves and a heavy, pointed end falling down towards you. Safety glasses are often mocked by tough guys in our industry and others — they won’t save you from a chainsaw cut.
But they could save your vision, especially for smaller pruning jobs. When you make cuts with a pole pruner or hand saw, you’re often looking right up at the branch. Even a tiny branch falling straight down and hitting your eye could cost your vision. It is very painful to have a branch hit anywhere around your eye — trust us, we made the mistake a long time ago so you don’t have to.
Pole Pruner or Pole Saw vs Ladder
A pole pruner and a pole saw are very helpful to avoid getting up on ladders. Ladders are a leading cause of injury to homeowners and non-professional tree cutters. You get on a ladder, cut a branch and it falls on the ladder and knocks you off. Falling off a ladder can cause broken bones, and we are personally acquainted with a family friend who became paralyzed from the waist down falling off a ladder in his own backyard. Because tree branches are heavy, swing and move unexpectedly, a ladder forces you to be right where they may fall. As professional arborists, climbing is often much safer for us, even for small trees, because of this.
Putting a ladder against a tree and cutting branches is a very bad idea. Some of you will do this anyway, but please do extra research on trees and risks if you do so you can adequately prepare.
Chainsaws: Know Your Tool
The second leading cause: Chainsaws. You can easily buy a homeowner chainsaw at the store from trusted brands like Stihl or Husqvarna or Echo. Milwaukee and Dewalt also offer 20v battery saws — but buyer beware, electric saws cut through even the best, professional chainsaw protection. We have seen it specifically with Milwaukee.
Great care should be used on saws with no “inertia brake.” This is a brake that stops the chain if the saw “kicks back”. When you touch the tip of a chainsaw on something, the force of the chain movement can cause it to flip backwards torwards you. An inertia brake registers that sudden movement and can stop the chain. Saws without one will not stop in the common, and likely, event that you experience kickback.
None of the homeowner-grade saws offer anti-vibration protection, meaning that they are very bad for your joint, blood vessels and nerves to use for extended periods of time. Raynaud’s disease, or “white finger disease,” is an occupational hazard for arborists, even when using top of the line saws. If you’re cutting firewood or other wood by yourself frequently, you should invest in a saw with anti-vibration protection, and a pair of chainsaw gloves.
Lastly, please use a chainsaw only when someone else is around and when you have adequate first aid supplies to deal with an injury.
A Word on Ropes
We hope you won’t be needing to use a rope, because that would mean either heavy wood or working at heights. If you choose to do this, please read this physics lesson first. The biggest thing you must understand is the weight the rope can withstand (breaking strength), the weight of the wood (green log weight), the techniques to reduce load (friction adding), and cycles to failure. Don’t buy a rope that has a max breaking strength of 500lbs if you plan to use it for something heavier than 50lbs (10% of max).
When wood falls into a rope, it is rapidly decelerated and this majorly increases the load (or the force of the weight) on the rope. The rope may hold the first time, or many, but over time, a rope experiencing repeated excess loading will fail. This is called cycles to failure, or the number of times you can us a rope before it breaks. The number decreases dramatically the higher the load.
Even small branches can easily fall and cause significant damage to your eyes, head or feet if they are unprotected. If using a chainsaw, steel toe boots, chainsaw pants or chaps, ear protection, eye protection, gloves and helmet are required. We do not recommend or advise using a chainsaw. If you do use one, do not use a chainsaw alone, on a ladder, and without proper knowledge or instruction.
5. Why Is Tree Trimming Important?
Since you likely came here looking for DIY tree trimming services in Toronto, you may already know that pruning is the best way to keep your tree looking good, safe and healthy. Many large dead and broken limbs hanging in trees can be hazardous if people or pets are underneath the trees on a regular basis.
Trees growing in the urban environment are subject to a lot of stress, but also lots of sunlight. They may become overgrown, overextended over top of your house, or have too many branches and limbs to grow properly into the future.
DIY tree trimming can be a way to handle a small problem you may have, like a branch that sticks out onto a path, but if you find yourself cutting the tree over and over again, it would be best to call in an arborist. We often get called to work on trees that clients have been cutting themselves for years. These trees have problems.
Sometimes we can help, other times the damage to the tree is too extensive and results in costly removals. Many people do DIY tree trimming to save money, and that’s totally fine. But make sure you do your research to understand the science of trees a bit more so that you aren’t saving a small amount now only to create a very expensive problem for yourself later.
Frequently, DIY tree trimming has caused wounds and rot in the tree, or resulted in large bare patches in the tree that cannot be fixed by pruning. These issues could have been addressed with a quick, inexpensive visit. Small jobs to remove a few branches can be done at low cost every couple of years, preserving the look and value of the tree without compromising your safety.
If you’d like advice on tree trimming, or if you started a DIY tree trimming project and want some help, give us a call at 416-757-0505 or contact us for a free consultation.