A very common problem that often affects trees and plants in Ontario is salt damage. Salt is used on the roadways and sidewalks, and can cause plant damage in two ways. The first way is that the salt contaminates the ground around the plant. The second is that salt damages a tree when it is sprayed on the foliage or buds.
Trees within 30 ft of roads and walkways experience the most damage. Salt which is spread on the roadway often sprays up on the buds and foliage causing a lack of moisture, which in turn burns the tree. Then when spring arrives when the tree is in need of water, salt works its way into the soil causing the tree to become unable to obtain necessary water.
Though salt damage in an urban environment is not totally understood, it has been determined that some species have a higher tolerance then others. For example Honey Locust with its waxy branches and protected buds are more likely to survive, then a White Pine. It has also been determined that some species such as the White Cedar can tolerate salt in the soil, but not on the foliage.
If you have salt damage it is often a good idea to fertilize and water regularly. This will often reverse the damages cause by the salt. Also if a tree is damaged it will often put up water sprouts or sucker branches as it is distressed. These branches should be trimmed before they become too large.
If you are planting a tree near a road way, and you are concerned that it may become damaged, it is possible to use a planting pit. Though a planting pit is not always effective, it often can help, allowing the tree to obtain the necessary nutrients.
If you have a question, you can email me at firstname.lastname@example.org, and I will respond either by email or in a future article. If you would like me to come and assess one of your trees, you can call me at 519-272-5742.
Joel Hackett is a Certified Arborist Residing in the St Mary’s Area. Spending most of the year running Joel’s Tree Service, he also teaches Arboriculture during the winter at Lambton College. Joel Hackett does not assume any Liability for any information in this article.