Signs of Tree Failure to After a Windstorm?

The trees that are most prone to failure are large conifers, stand-alone trees, trees in a very wet area, and street trees.


The Pacific NW is full of large conifers and they thrive here. I have seen growth rings on firs that are close to an inch wide per year. If you add all that up over the whole organism, it is a lot of weight per year. Trees tend to grow slower in the beginning of their life, then they shoot for the sun. As they grow taller they are affected by stronger winds, and if not regularly pruned for sail reduction they become ticking time bombs (especially when you have a winter as saturated as this year’s.)
The root structure of a mature fir is not as big as you would think. The trees evolved over millions of years to live in a forest where the roots from many other trees co-mingle and make a strong mesh that holds them all altogether.

In an urban environment when you have a stand-alone fir or firs they take the brunt of the force from wind head-on.

During a windstorm steer clear of large firs and conifers. Don’t walk underneath them or downwind from them because debris can fall out suddenly and can be blown long distances. After the storm, take out a set of binoculars and study the canopy of your conifers. Look for downward pointing branches (aka “widow makers”) and “white eyes” along the trunk of the tree – this is an indication of freshly ripped off branches. If you don’t have any debris on the ground then they are still up there waiting to fall. After you have done a thorough inspection of the crown and have determined that it is safe, you can go and walk the dripline of the tree. The dripline is the circumference of the furthest reaching branches of the tree.
Walk this area in a grid and look for upheaving or cracked ground, and exposed roots — all signs of imminent failure.

If you have any questions or would simply like a certified Arborist to look at the crown and dripline, please give me a call. Inspections are free!

Stand-Alone Trees

The next culprits we have are trees that are standing alone. While these trees do not have the advantage of the forest, they have room to grow and spread their roots. After the windstorm study the canopy or “crown” to make sure there are no hazards, then walk the dripline and look for signs of change in the topsoil. If the tree has not been pruned in awhile (every 3-5 years is recommended for mature trees), then call a certified Arborist.

Trees in Standing Water

Next we have trees in standing water. Trees in water are essentially being drowned unless you have a mangrove on your property (which I’m sure is not far from reality this year!)
The roots begin to rot after time and put out a swampy smell. My first recommendation is try to figure out the drainage issue and remedy it by installing french drains or a simple ditch lined with rock. If the tree is large or leaning and it has been like this for some time, give me a call and I’ll come check it out.

Street Trees

Street trees are the most likely to fail — especially ones near recent concrete repair because the roots were probably cut during construction. Some good news is that typically they are small and far away from structures. While cities and counties technically own street trees, it is up to the homeowners to take care of them. Some signs of failure to look for are a change in angle of the tree and uplifting sidewalk.

Be safe out there! We have a lot of large beautiful trees here to enjoy, just make sure you’re not sitting under a killer.

Don’t be shy about requesting a free inspection!

Stephen Gibson
Certified Arborist PN-7339a