Trees are rather permanent features of your yard and should be chosen with some care.
The most important advice I can give is to choose smaller trees.
Aesthetics: A large tree can overpower a house. Your house is part of the landscape and all elements should work together, both living and non-living. Your goal is to complement your house and use its height as well as its colour, texture, and drama (e.g., narrow and tall) to add interest. Trees can also be used to frame or block views, but if the tree is very large, you may block more than you intended. When we moved into our current house, the previous owner had planted four Colorado spruce along the back fence. But because they could potentially block the view into the park, she advised us that she needed to hire someone to shear them twice a year to limit their height and spread. Twenty-year-old spruce should have been 20-30 feet tall and 10-15 feet wide, but these were perfect cones, at most 15 feet tall by about eight feet wide. One of the first things we did that fall was prune them to the ground and replace them with supposedly disease-free and non-suckering aspen (they were neither, as it turned out).
Safety: If a branch breaks off or the whole tree falls over due to age, disease or wind, you don’t want it to fall and crush your house, garage, car, fence, etc. A few years ago, the neighbour across the alley had very large poplars lining the back of their yard. A plow wind came through and knocked over two. Fortunately, the trees fell across the alley, not towards the house. But they blocked the alley until city crews showed up the next week. Damage (this time) was limited to crushed fences.
Function: Trees reduce wind, create shade, and can reduce cooling costs in summer. Short to moderately tall trees provide these functions as much as very tall trees.
Removal: The larger the tree, the more expensive it is to hire someone to take the tree down, chop it up for firewood, or take it to the landfill. And, if you intend to replant, removing the stump and roots can be challenging (also expensive).
My second piece of advice is to know what you’re planting.
Function: Consider what you want from your tree. Trees can provide shade, frame or block a view, produce food, perfume the world, add texture and colour, provide habitat for birds, and create drama.
Characteristics: Know the height, width, hardiness, drought and flood tolerance, water and soil requirements, fall colour, leaf colour and shape, flowers, scent (personally, I love the smell of lindens in bloom but not Russian olives), fruit, seed type (and amount), fall colour, etc. Some tree species can either be diecious (have both male and female flower parts on the same tree, e.g., pine) or monecious (separate male (produce pollen) or female (produce seeds) trees, e.g., green ash). Growth rate is often mentioned as an important consideration. However, fast-growing trees can be shorter-lived and have ‘weak’ wood (i.e., prone to broken branches). And ‘slow-growing’ trees can still add a foot or more per year – the burr oak in my front yard does not know it’s supposed to be slow.
Avoid potential problems: Choose trees that are resistant to disease and insects; produce none to few suckers; have limited seed production (e.g., avoid trees that produce ‘fluff’, drifts of seeds, heavy loads of acorns, etc.); and opt for dwarf varieties when possible.
My third piece of advice is to realize that you are not alone.
Although you can do what you want in your own yard, within reason, the trees in your yard are part of the so-called urban forest. Consider the larger landscape and whether you want to stand out or blend in with the neighbourhood – either is fine, but be purposeful. Also, consider how your trees will impact your immediate neighbours: will your neighbours appreciate large branches hanging over your shared fence (and will they take it into their own hands to deal with that)? Will they thank you for the forest of suckers that have appeared in their beds and lawn? How much unplanned/unwanted shade will they receive from your trees? And while the wind distributes and redistributes leaves from near and far, what will they think about the ‘free’ fruit and seeds/acorns that they need to clean up from your trees?
My final piece of advice is, “The best time to plant a tree is twenty years ago. The second best time is now.” (Anon)
Erl gardens in Saskatoon
This column is provided courtesy of the Saskatchewan Perennial Society (SPS; saskperennial@hotmail.com). Check our website (www.saskperennial.ca) or Facebook page (www.facebook.com/saskperennial) for a list of upcoming gardening events.
