One of the perks for homeowners in King and Snohomish counties is the urban forest that surrounds them. The towns and cities of the Puget Sound—Seattle, Kirkland, Lynwood, Woodinville, Everett, just to name a few—are filled with tree-lined streets. But could some of these trees become more of a hazard than a shady canopy?
What makes a tree hazardous?
Within the professional tree care industry, a hazardous tree is defined as a tree with a structural defect that poses a risk to life or property should it fail.
Not every damaged tree is a hazardous tree; in fields and forests, damaged trees topple on a regular basis without ever being classified as hazardous. These trees simply fall to the ground, perhaps impacting nearby trees and shrubs on the way down, but no property damage.
But in an urban setting such as the densely populated, small-parcel neighborhoods of Seattle and its outliers, the likelihood that a falling tree will impact nearby structures, pets, vehicles, or people is much, much higher.
How can you tell if your trees are hazardous?
Take a look at the trees on your property and see if they have any of the following symptoms of structural defect:
Split trunk — This could be caused by lightning, frost, impacts, or age.
Leaning trunk — The steeper a tree leans, the more likely it is to fall over completely.
Stem damage — If the bark and wood at the base of the tree are injured, it damages or destroys the tree’s ability to move nutrients and hydration from the roots up into the trunk and canopy. A tree with deep stem damage only has so long to live before it begins slowly dying.
Deadwood — A tree with a significant amount of dead branches is either dying or in severe distress, both of which make it more vulnerable to being blown over by a strong wind or dropping those dead branches unexpectedly.
Cracked or sloughing bark — If large pieces of bark, and/or the sapwood just underneath it, are peeling away from the trunk of the tree, that’s a problem! Like stem damage, sloughing bark interferes with the tree’s ability to transport nutrients. It is often a sign of infection, or it can easily become a site of infection due to being a large open wound on the tree’s outer surface.
Cankers — These are sunken areas in the wood of the tree where pathogens eat into the sapwood and eventually the heartwood of a tree. Cankers usually occur inside of the wound of a poorly done pruning cut (another good reason to hire a certified arborist for tree trimming). Some cankers are annual, and the tree is able to kill off the infection before they cause too much damage; others are perennial and persistent, slowly encroaching further into the tree and making it more vulnerable to other diseases and infections.
Root disturbance — If you can visibly see the root system of the tree lifting out of the ground, that’s definitely a cause for concern! A tree with lifted roots is no longer able to anchor itself and will struggle to efficiently transport nutrients and water from the soil through its compromised roots and into the trunk. Similarly, a tree with decaying or damaged roots will lose its firm hold on the earth as well as slowly begin to starve.
Co-dominant stems — Trees are strongest and healthiest when they have one strong central trunk. A tree with two central stems is more likely to break or fail in extreme weather events and may also be more susceptible to disease.
Irregular crown — A misshapen crown with limited leaf cover is symptomatic of greater stress within the tree itself. A healthy tree will have a full canopy with abundant leaves to drive the photosynthetic conversion of sunlight into much-needed sugars. But a tree that is unable to produce many leaves due to stress, disease, or other damage will be further handicapped by a lack of photosynthetic sugars.
Other considerations
You should also take note of your trees’ proximity to obstacles, such as:
- Houses
- Garages
- Shops or outbuildings
- Street parking
- Power lines
- Fences
- High-traffic walkways or sidewalks
A tree that is planted very close to a house, fence, or other structure may someday pose a hazard by growing into it or dropping branches down on to it or, in a worse-case scenario, falling down onto it.
Similarly, a large tree with structural defects growing close to a power line could fall and snap the line, creating an exceptional hazard.
So, if you notice these symptoms or other problems, what’s your next course of action?
What should you do with a hazardous tree on your property?
First of all, determine if the tree is in imminent danger of falling. If it is, then you should reach out to Elite Tree Care for its 24-hour emergency tree service to take care of the tree before it can fall and cause damage.
If the trees in question are damaged but not dangerously unstable, it’s a good idea to have a certified arborist come to your property and conduct a Tree Risk Assessment.
What is Tree Risk Assessment?
A tree risk assessment is, in general terms, the evaluation of a tree to judge its hazardousness. It is a specialized category of tree care.
If you are searching for an arborist in Seattle or the surrounding areas to inspect your tree, look for one that has earned the International Society of Arboriculture’s Tree Risk Assessment Qualification (ISA TRAQ).
This qualification requires that arborists complete a training course, pass a written test, and pass an assessment of performance in the field. To maintain this credential, the arborist must retrain and retest with the ISA every five years.
Tree Risk Assessment following the ISA’s standards involves a detailed evaluation of the site and soil conditions of the tree; of its exposure to wind and other environmental factors; of its trunk, crown, branches, and roots; and of the health standards and expectations of that tree’s particular species.
An arborist who has achieved the ISA TRAQ is a highly skilled, comprehensively trained, and experienced individual who can make accurate diagnoses and expert recommendations.
If you’re a homeowner in the Puget Sound area concerned that damaged trees on your property may cause a risk to life and limb, reach out to Elite Tree Care today at (425) 350-6909 for professional Tree Risk Assessment services. Our ISA TRAQ-certified arborists conduct assessments of potentially hazardous trees by visual and aerial means and, if necessary, with advanced inspection technologies like sonic tomography and resistograph measurement.
Call Elite Tree Care today for a free estimate or to schedule an appointment with our expert tree specialists! We serve communities in King and Snohomish counties including Seattle, Kirkland, Everett, Bothell, and Lynwood.