Now that spring weather is upon us it is a great time to turn our attention to the care of trees and shrubs in our landscapes. Our woody plants are often overlooked for the many benefits they provide. Try to imagine your property without its trees and shrubs. No cooling shade or privacy screening, no contrast to all of the concrete and asphalt not to mention the beauty in all the colours and interesting shapes of our woody plants. Given the value that trees and shrubs offer, it is important for us to provide the care that will allow them to thrive in our harsh urban environments.
I would invite you to take a walk around your site and make a few observations that could make a world of difference to your trees. At the very least you will be getting a breath of fresh air and a little mind clearing exercise!
Look at the base of your trees. Can you see the root flares? This is the area where the trunk is widening to form roots.
If the area is not visible you may have a tree that has had too much soil or mulch mounded against its trunk. This condition can cause a vascular rot in that basal area of the tree because the trunk tissue above the root flare is not designed to withstand constant soil and moisture held against it. This condition can also promote the growth of encircling roots that can strangle (girdle) the tree causing decline and death. If you cannot see root flares or you do see encircling roots on any of your trees, they will require the attention of a certified arborist. By correcting these conditions, you will be making the difference between trees that struggle to exist and trees that have the opportunity to perform well in your landscape.
Don’t look up yet, we are not finished with the root crown of your trees. After all, this is one of the most important areas of tree anatomy!
Is there grass growing against the trunk of your trees? If yes is your answer, is the trunk being damaged by lawn mowing equipment? We cannot expect our trees to be strong, healthy and beautiful when large portions of their vascular tissue are missing! We also don’t want our trees to have open wounds in a critical area where insects and fungal pathogens could cause significant damage. This condition is not hard to correct. Simply have the layer of sod removed from around your tree and install a 5–10 cm layer of wood chip mulch. Be sure to keep the mulch 10–15 cm away from the trunk of your tree. The wider you make the mulch ring around your tree, the better it is for the tree. You are creating a soil environment that mimics the decomposing litter layer found in a forest!
Ensuring your trees and shrubs are properly mulched is one of the most beneficial practices you can employ for improving their health.
Still looking at the lower trunks of your trees? Check to make sure rodents, insects or fungus have not caused any damage. A certified arborist should be consulted if you see any problems.
If your trees have any stakes and guy wires, perhaps it is time to remove them. You do not want any guy wires to strangle your trees. These are often overlooked in newly planted spruce and fir trees, however, all trees should be checked.
I would like you to check one last thing. Are salt laden snow or de-icing salts being plowed or broadcast over the root zones of your trees? If this has occurred, an application of agricultural gypsum with deep watering can be performed to help leach the toxic salt below the root systems. Talk to your snow contractor about future strategies to prevent salt damage to your plants.
I look forward to sharing more tips for healthy trees and shrubs another time.
Ken Lund has over 45 years of experience in arboriculture. As the president of Four Seasons Tree Care and Service Ltd. Ken brings with him expertise in all aspects of tree and shrub care. He is a founding member of the Ontario Commercial Arborists Association serving as the treasurer for 16 years. fourseasonstreecare.com
