Wind, wind

Garden Clippings for July 29, 2023

Among the many trees that went down on Thursday, July 20, was a huge White Pine on the property of Dunlop Central United Church.  Several years ago, the White Pine was identified and labelled by the Arbour Week Committee as a Tree of Distinction, one of about 40 Lambton trees that enjoys the honor.

Windstorms or hurricanes don’t discriminate.  They will destroy trees regardless of size, variety, location, or condition.  If there is a tree in the flight path of a storm, there is a good chance that it will fall victim to severe weather, while another tree just a few feet away might survive unscathed.

At first thought, it would make sense that unhealthy trees would be most vulnerable to wicked winds, but the opposite is true.  A healthy, dense tree with big leaves catches more wind than a weak tree with smaller leaves.  As a comparator, think of holding up a solid door versus a screen door on a windy day.

City streets, parks and backyards were littered with smaller branches fallen out of large trees.  Most fallen limbs were Silver Maple, Manitoba Maple, Poplar, Tree of Heaven and other weak wooded trees.

Oaks, hard Maples, Walnuts and other hardwood trees are more vulnerable than Willows, Poplars and Mulberry, because strong wood can snap, while the latter have limbs that are pliable.

There is no such thing as fully hurricane proofing your yard or landscape, but steps can be taken to reduce the danger to trees and homes from severe storms.

Urban areas and streetscapes often have disturbed soil that doesn’t allow for good root development.  New subdivisions will bulldoze and replace subsoil, adding a final thin layer of topsoil, barely enough to support good grass growth.  When planting trees, it is important to dig large holes, mixing good soil with some of the existing subsoil.

Place trees far enough away from houses, driveways, sidewalks and roadways. Trees that have structures nearby are more vulnerable because their roots cannot spread in all directions.

Avoid watering too much.  Gardeners who water the lawn frequently should put away the hose periodically to encourage tree roots to go down in search of moisture.  Trees that receive too much water will develop lazy, shallow roots.

Plant trees in groups.  Large growing trees entangle their roots together, forming a network of roots that rely on each other for strength.  There truly is strength in numbers.

Choose tree varieties carefully.  Native trees are generally stronger than imports and are suited for wide open areas.  When planting in tight locations on boulevards adjacent to roadways and sidewalks, choose trees that suit non-native environments.

Keep in mind that the biggest trees are most vulnerable.  The White Pine at Dunlop Central United Church was one of Sarnia Lambton’s tallest trees.  Conifers tend to grow tall, catch much wind, and have shallow roots.  Hardwood trees are sturdier than their softwood counterparts.

Finally, homeowners and municipal workers should continue to plant more trees.  Trees in both urban areas and forests have longevity but will not last forever.