Posted by: Mary Johnston
In June 2022, Dr. Andy Kenney (professor emeritus at the U of T School of Forestry, and author of the Neighbourwoods Inventory) kindly came to Old Ottawa South to host another successful tree workshop. This gathering was to learn the basics on planting trees.
With extreme weather events occurring across the globe, and locally here in Ottawa, the time to plant trees is now. Although the city plants tree, 80-90% of the urban environments is private land. This includes not only our own backyards but also businesses and schools. We can effect change by looking to these private spaces and planting trees. The bigger the tree the better, although every tree has benefits. So, as a call to action, look in your backyard and see if you can help the environment, one tree at a time!
At the workshop, Dr. Kenney reviewed the basic steps for successful tree planting.
Choice
Tree choice is an article in itself (native vs non-native vs invasive) and his main recommendation is simply: avoid invasive species.
Location
After identifying a location for a tree, dig a hole that reflects the depth from the first top root to the bottom of the root bulb. Sometimes the first root is under the soil in the pot. You need to identify it and keep it visible when backfilling the hole, even if it was buried in the nursery pot.
Protect roots
When digging the hole, try not to break roots of existing trees. Although trees can survive even if 10-15% of their roots are eliminated, if you don’t need to cut them, don’t. If you do need to cut roots of another tree to accommodate the new one, make sure you use a clean knife. Don’t chop it with your shovel. This is an open wound for the tree. Make a clean cut, so it can heal quickly and will not be a gateway to infection.
Free roots
When placing the new tree in the hole, first unwind and free the roots that are typically swirling inside in the nursery pot. Fill around the roots with the soil taken out when digging the hole. Newly purchased garden soil may disrupt the transition of moisture and nutrients from the surrounding soil to the tree roots. As you refill the hole, avoid air pockets and water well. Remember that the first root should remain visible and level with the ground.
Mulch
At this point, you may consider adding mulch on top to keep down weeds and trap moisture. Best choices for mulch are bark or cedar chips. Coloured mulch is made from old palette material and treated wood, so best avoided. You can add mulch up to 10 cm. Don’t put it directly next to the trunk, rather keep a 15-20 cm radius free of mulch. Most important, mulch keeps ‘weed eater’ machinery away from trees, avoiding damage to the bark, which can be deadly to trees.
Prune and water
Finally, it is important to prune each year and water a newly planted tree for the first 2-3 growing seasons. After this, trees generally only need extra watering in times of drought.
Dr. Kenney is a wealth of information on anything tree related, and we learned so much more! Special thanks to Sandra Gillis and Viviane Templeton for helping to arrange this valuable workshop. If anyone wants to talk about (or act on!) planting a new tree on private land, please contact a member of the Tree Team, or email odard@bell.net
Mary Johnston is a resident of Old Ottawa South and a member of the Enviro Crew’s Tree Team.
Featured in the September 2022 OSCAR.