How to prune standard size pear and apple trees?
Training and pruning fruit trees from an early age plays an essential role in their future health and productivity. Structural pruning has the effect of creating a good structure, balance, and aesthetic, all the while facilitating the ease of future harvesting.
The training technique presented here is that which we use on our pear and apple trees. It is applicable to all full size pear and apples, also known as standard trees (dwarf trees require different training techniques).
This technique can also be applied with most other trees of large stature. For more ornamental trees such as: walnuts, maples, oaks, basswoods, etc., one could opt for greater spacing between branches and a canopy starting higher off the ground.
A myth regarding how trees grow
The branches of a tree move up as the trunk grows. True or false?
Many people find that a little tree with plenty of branches is more attractive and believe that as the tree’s trunk grows taller, these branches will ascend with it. This however, is not the case.
If a young tree has a branch at 30 cm from the ground, this branch will not move higher as the tree grows. It will remain at 30 cm from the ground and the mature tree will have an enormous branch at 30 cm from the ground, if it is not broken by the snow long before.
If we want to one day be able to sit in the shade of this tree, hang a swing, or simply pass the lawnmower underneath its canopy, it is necessary to remove these lower branches.
When should pruning be done?
The time for pruning fruit trees here is in March or April. What is important is that the major cold weather is finished but the trees have not started to flower yet.
This is also the time to prune most other trees, with the exception of birches, maples, and walnuts, all of which are prone to sap bleeding, which can have damaging consequences.
How to train a fruit tree
Training is the practice whereby the future size and form of the tree are determined. It is best started from a young age. Training entails choosing the positioning of each of the principal branches to attain a balanced structure.
Training is not an exact science. There are many ways to go about it and multiple professionals would likely make different choices regarding which branches to keep if asked to train the same tree. There is no need to overthink it or stress over it. It is sufficient to have an understanding of the general principles and have confidence in your decisions. In the end the tree will be fine.
Choosing the height of the first branch
The first step is choosing the height of the first branch. Here it is important to take a moment and think to the future. What environment are you looking to create 10, 20 years down the road?
Do you want to be able to sit it the shade of this tree?
Pass underneath its branches with the lawnmower?
Hang a swing?
Place a picnic table?
Knowing the desired end result is critical to making the appropriate choice.
Another important factor to consider is the accumulation of snow during the winter. The lowest branch should be at least 30 cm higher than the maximum accumulation that is possible.
For example: here in Rawdon, we can get up to 1 meter of snow accumulation during the winter. The lowest branches of our trees are always at least 1.3 metres from the ground.
On the other hand a person who lives in Toronto and only has a maximum of 60 cm of accumulation could decide to have their lowest branch at 90 cm from the ground.
Once the height of the lowest branch is determined, all the branches below this height can be removed.
Breakage by the snow
Here is an example of a plum tree that has had a branch broken by the snow.
Snow and ice trap the branch and can tear even large branches away from the trunk when melting.
The reason we recommend leaving 30 cm between the snow and the lowest branch is that over time the weight of fruit will cause branches to develop a downward curve and the end of the branch will be lower than the level at which it meets the trunk.
Choosing which branches to keep
The next step is choosing which branches to keep. The ideal for apple and pear trees is to keep one branch at each 30 cm interval on the trunk.
We also want them to be well distributed around the trunk. A simple way to do this is to pick one at each cardinal point. For example, if we want our first branch 1 metre from the ground and there is a branch at this height pointing north, we keep it. We then look at what branches there are about 30 cm higher and if there is a good-looking branch pointing south, we keep it. We continue looking to each 30 cm interval to find one pointing east, and then west.
Once these principal branches are chosen, all the rest can be removed with well-sharpened pruning shears.
Disinfecting tools between cuts
Prevention is always better than intervention. Between every tree, disinfect your tools with alcohol. This will help prevent the spread of any diseases that might be present.
Where to make your cuts?
When pruning, we want to make our cuts just above the collar between trunk and branch. This area contains chemical compounds that help resist disease and facilitate healing
If we cut too far out from the collar we leave a little stub of dying wood that delays healing of the wound and can be an entry point for disease
If we cut into the collar it opens the door for moisture and disease to make their way in.
How to properly use a bypass pruner?
For pruning, the tool that we recommend is the bypass pruner. There is in fact a proper way to cut with bypass pruners to obtain a clean cut. Like a pair of scissors, bypass pruners are made up of two blades that pivot and cross to make a cut.
However, where scissors have two sharpened blades, bypass pruners have one sharpened blade and a counter blade that is not sharpened.
It is this mechanism that allows us to make clean and precise cut without tearing.
Take note though, to make a clean cut it is necessary that the counter blade be on the side of the cut that we are removing and not the side we want to keep.
If we place it the other way around we crush the part that we are keeping and make an injury that is more difficult for the tree to repair, increasing the risk of disease.