Pruning a mountain ash in early April, Red Deer. R.LePage photo.

Why should we prune trees?  At a very basic level, the purpose of pruning trees and shrubs is to ensure healthy, vigorous plants.  We achieve this simply by removing diseased, dead, and damaged branches.  But there is much more to pruning, and the pruning needs of each plant must be assessed individually, according to location, species, and purpose in the landscape.

All trees need some kind of formative or structural pruning, to ensure a healthy, strong branch architecture that will resist storm damage, and lessen the need for drastic pruning intervention as the tree matures.  It is much better to make small cuts on a young tree than very large cuts on mature trees.  The larger the pruning wound, the more difficult and slow it is for the tree to resist decay.  The pruning process for young trees should start the season after they are planted, and such trees will require a few cuts per year for their first few years of growth.  After that, many species will only require occasional pruning throughout their life, especially if the tree is planted in an appropriate location, and the intent for the mature specimen is to remain in a natural form.

Over the years, I’ve found that landscapers and homeowners generally make the same mistakes when planting trees.  That is, they very often plant them far too close to buildings, neighbours, alleys, walkways, and to other trees, and therefore require pruning every couple of years to address clearance concerns.  That cute little spruce tree looks good in front of the living room window when it’s only 8 feet tall, but 20 years on, and 30 feet later, it can be a very different story.  Clearance pruning requires skill in that, after pruning, the tree should still look as natural as possible, without hard, obvious cut lines, or mutilated limbs.

In older neighbourhoods especially, we often encounter trees that have been carelessly mutilated by homeowners, their neighbours, or what we call “tree cutters,” those unskilled, under-educated folks who clog the yellow pages under the heading Tree Services.  Beware the tree cutters, and always make sure that when hiring landscape contractors, either for tree work or otherwise, that you find reputable businesses with certified, educated professionals.  In our industry, the most common credential is called an ISA (International Society of Arboriculture) Certified Arborist.  Don’t be afraid to ask for credentials.

Restoration pruning addresses the need to “fix” mutilated or storm-damaged trees.  Often, seemingly destroyed trees can be restored over a period of several years, and a few pruning cycles.  It may be quicker and less expensive, in the long run, to restore a damaged tree, than to replant a new one and wait many years for it to grow to a suitable size.  While restoration isn’t always possible, it’s a good idea to find out if it is.

The final reason we prune trees is also the most complicated, and requires the most skill, knowledge of plant species, and years of experience.  And that is pruning to improve the natural appearance of trees and shrubs, enhance flowering, branch architecture, or shape, increase or decrease fruiting crops, or to create balance, contrasts, uniqueness, and flow within a beautiful landscape.  It is here that science overlaps with art, and where the technical arborist also becomes the artist.  And just as all artists have distinctions in their methods and style, so to will you find with the skilled ornamental arborist.  Very technically pruned trees are not low-maintenance and were never intended to be, and often require annual maintenance to remain specimens.  When hiring a professional to prune your trees, be sure to ask what the pruning requirements of your plants will be, so as to avoid surprises later.

Also, when hiring an arborist for very creative-type pruning, be sure to ask for example photos or an address or two that you can drive by and look at.  High maintenance pruning may require more from an arborist than just being ISA Certified.  And ISA Certification alone does not necessarily mean that the arborist has any practical pruning experience, only that they have sufficient knowledge to pass the exam.  Be sure to ask questions.  It’s your tree and your landscape!

For specific information on tree and shrub maintenance, enter the name of the plant in the search bar above.

For any other information on pruning, please feel free to contact our office at (403) 755-5899.

(c) 2011 Shane LePage, Wild Rose Garden & Tree Service