Trees provide many benefits to a property, such as shade from the sun, sound and pollution absorption, and a dose of nature in what might otherwise be stark urban environment. Residents can also become emotionally attached to particular trees, so the decision to remove one can rarely be taken lightly. As dynamic organisms, trees (like animals and humans) have a finite life expectancy and their physical condition can change, sometimes very quickly. They can become dangerous as they decline in condition, so it’s important to make objective tree removal decisions.
There are many reasons to remove a tree. Dead specimens are usually the most obvious, as are those that have suffered catastrophic storm damage. But sometimes the signs of a weakening tree can be more subtle. Canopy die-back can signal root decay, as the tree struggles to maintain its above-ground biomass with a shrinking root crown, and a seemingly minor swelling in the lower trunk can signal the presence of a dangerous level of internal decay. Trees that have come in at an angle usually do a good job of growing sufficient roots to remain stable, but those that suddenly develop a lean (due to high winds, for example) may be on their way to tipping over.
There are also situations that call for the removal of healthy trees. Arborists are often asked to advise property owners and managers on pruning trees that have outgrown their limited space. It may be more effective to remove such trees and replace them with a species that has a smaller mature size than to enter a cycle of expensive pruning that leaves the tree mutilated. Owners should also consider the long-term useful life expectancy of an existing tree when undertaking landscape renovations, as a lot of time and effort can be spent preserving a tree that might only live for another five years.
Consider engaging a certified arborist (ideally holding the ISA Tree Risk Assessment Qualification) to carry out an inventory of the trees on the property to help guide these decisions. The arborist’s report should objectively document tree condition and suitability for retention, and can then be used to build a longer term tree-management plan for the property. The arborist should also visit the property after storms to identify any trees that have been affected by the weather. This also helps to head off knee-jerk reactions where every tree is considered dangerous because of its size and over-zealous news reporting.
After deciding that a tree needs to be removed, consult local bylaws to see if a permit is required. Most municipalities exempt dead or imminently dangerous trees, but they usually need to be informed so that they can check the tree for themselves and issue an exemption certificate. Also confirm who owns trees that are on or close to a boundary, contact the neighbour and include them in the removal decision. There might not be a legal requirement to inform residents about plans to remove a tree, but it can often help to soften the blow of losing a favourite specimen and can help avoid recriminations later.
A tree removal permit may stipulate tree replacement as a condition, or replacement might just be something the property owner feels is the right thing to do. Canadians living in cities are fortunate that previous generations saw the need to plant trees in streets and parks. By replacing lost trees, this generation can do its bit to preserve the urban canopy for future generations.
When planning tree planting, consider the desired long-term function of the tree (shade, screening, flowers, fall colours) and how much space is available above and below ground. Ideally, plant trees that are well-matched to the local environment (shade, moisture, soil characteristics) and that will need minimum inputs (pruning, watering) during its life. Choose good quality trees from a reputable grower, and don’t always go for the biggest tree that the budget will allow. It’s common to see large, expensive trees struggle for several years after planting, only to be outgrown by the smaller trees that became established that much sooner. And only plant as many trees as the corporation can afford to maintain for the first three years, as this is typically how long it takes to establish a tree in an urban situation. Nothing says neglect (and a huge waste of money) like dead, newly planted trees.
Managing a property’s trees in a proactive and planned manner should help to avoid much of the emotion and conflict that can arise from tree removals. Coupled with a sensible and well-thought-out replanting program, the property’s trees can be an appreciating asset rather than an unquantified liability.
Craig Southwell is an ISA Certified Arborist and an arborist representative at Bartlett Tree Experts.