Thursday, December 11, 2014

Trees and Storms


40-50 mph winds + several inches of rain over a few hours = the recipe for a typical winter storm in much of California. 


TV news crews rush to the most photogenic damage during these rare occasions: downed trees, usually leaning against a house or crushing a car.

Without the correct care of the trees on your property, winter storms and trees will not get along. Most susceptible are the trees that keep their leaves year round, such as eucalyptus and camphor, along with the conifer family: pines, firs, redwoods and cedars. All that mass of greenery acts as a sail in a heavy wind, bending trees at ridiculous angles. Another cause of winter tree failure is crown rot, which despite its name, refers to the deterioration of the root system near the base of the tree. Combine that with a couple of inches of rain onto already saturated soils, and you have tree roots heaving towards the surface, leading to these pictures popping up on the TV news:


If this is the view from your window, the day after a major rain and wind storm is not necessarily the best day for the gardener to tackle the hazardous task of cleaning up the remnants of trees, shrubs and other plants that took a beating. If wind and rain is still in the forecast, the prevalence of slippery conditions and the chance of more falling debris should limit your cleaning chores to dragging broken branches away from the scene of the crime. It is not a good day to be climbing ladders or scrambling into trees while balancing a chain saw. Leave that to the professionals.

Arborists offer this good piece of advice for those surveying the fallen aftermath of a major storm: Limb failure is largely a product of poor tree maintenance over time. Take care of your trees, or they may take care of themselves in ways you won't appreciate.
According to the University of California publication, "Inspect Your Landscape Trees for Hazards", a nice day in autumn (or winter, spring or summer, for that matter) is the time to take an inventory of any possible future tree damage before you, your house or your car becomes the next victim of a falling tree or branch.

Leaning Trees: Are your trees not as upright as the result of recent heavy winds? Can you see newly upheaved roots or soil around those trees? Then, immediate action is required: call in a professional, certified, bonded and insured arborist to do an onsite inspection and offer a solution (find one near you at Newly leaning trees are an imminent hazard. 
If you have a tree that has leaned for a number of years, that tree can still be a hazard during wet, windy weather. Taking periodic photographs can help you determine if a greater lean is developing.

Multiple Trunked Trees: This co-dominant condition can result in breakage of major tree parts during storms. Usually, these trunks are weakly attached. Inspect the point where the two trunks meet; if you see splitting beginning, call in an arborist.

Weakly Attached Branches: Trees with many branches arising from the same point on the trunk are prone to breaking during wind storms. Prune out any split branches. Thin out multiple branches.

Hanging or Broken Branches: If you see storm damaged branches hanging from the tree, remove them as soon as possible. This includes removing any completely broken branches that may be resting elsewhere in the tree's canopy.

Cracks in Trunks and Branches: Measure the depth of any cracks with a ruler. If those cracks are more than three inches deep, call in an arborist to determine the best course of action.

Dead Branches/Trees: Branches or entire trees that have completely died are very likely to come tumbling down in a storm. Dead branches are most noticeable in the summer when the tree is in full leaf.

Cavities and Decay: Large, open pockets where branches meet the trunk, or at the base of the trunk, can mean big trouble. The presence of mushrooms on the bark or on exposed roots may indicate wood decay. Call in an arborist.

The Arbor Day Foundation website has this animated guide to proper pruning techniques.

Also: Tips for Hiring an Arborist. 

And, an illustrated guide for pruning large branches (which are branches that are greater than the thickness of your thumb): the three-cut method.


  1. And, in other news, the State Capitol Christmas Tree, which isn't planted in the ground and does not have a root system, is still standing tall.

  2. My tree is doing fine but then again, spent $1600 for a professional, certified, bonded and insured arborist, to prepare it for an El Nino year. I love my eucalyptus treen.

  3. All good advice but doesn't help if the tree isn't yours. My trees are fine. It's the oak in my neighbor's yard that is a problem. I'm quite sure it's a question of when it will drop a huge limb on my house not if.

  4. If tree isn't ours still we can make aware others who own it about the hazards it cause to you or others property due to storms. Each and every tree owner or tree's neighborhood should take precautions as the winter starts. They should trim or prune their trees before winter or as the winter starts.