Caring for Storm Damaged Trees

LA GRANDE – With last week’s snowstorm causing a localized downpour of broken branches, plenty of trees in the Union County area are looking worse for wear. Trees are surprisingly resilient but have their limits and it can be difficult to judge which ones are capable of recovery. Before property owners get chopping, the La Grande Parks and Recreation Department recommends reading up on Oregon Department of Forestry resources for post-storm care. The following information includes some recommendations and instructions from ODF:

Assess tree damage

• Other than the storm damage, is the tree basically healthy? If the tree is basically healthy, is not creating a hazard, and did not suffer major structural damage, it will generally recover with first aid measures taken soon after the storm.

• Are major limbs broken? The larger a broken limb is, the harder it will be for the tree to recover from the damage. If a majority of the main branches are gone, the tree may have little chance of surviving.

• Has the leader (the main upward-trending branch on most trees) been lost? In species where a leader is important to upward growth or desirable appearance, it may have to be a judgment call. The tree may live without its leader, but at best would be a stunted or deformed version of the original.

• Is at least 50 percent of the tree’s crown (branches and leaves) still intact? This is a good rule of thumb on tree survivability. A tree with less than half of its branches remaining may not be able to produce enough foliage to nourish the tree through another season.

• How big are the wounds where branches have been broken or bark has been damaged? The larger the wound is in relation to the size of the limb, the less likely it is to heal, leaving the tree vulnerable to disease and pests. A two- to three-inch wound on a 12-inch diameter limb will seal over with new bark within a couple of years.

• Are there remaining branches that can form a new branch structure? The remaining limbs will grow more vigorously as the tree tries to replace its missing foliage. Look to see if branches are in place that can eventually fill out the tree’s appearance.

• Is the tree of a desirable species for its location? If the tree is in the wrong location (such as a potentially tall tree beneath a power line), or an undesirable species for the property (messy fruit, etc.), it may be best to remove it if it has serious damage.

Caring for damaged trees

• Don’t try to do it all yourself. If large limbs are broken or hanging, or if high climbing or overhead chainsaw work is needed, it’s a job for a Certified Arborist. They have the necessary equipment and knowledge needed, and are generally listed in the telephone directory under “Tree Service”, or at www.pnwisa.org

• Take safety precautions. Look up and look down. Be on the alert for downed power lines and dangerous hanging branches that look like they’re ready to fall. Stay away from any downed utility lines-low-voltage telephone or cable lines and even fence wires can become electrically charged when there are fallen or broken electrical lines nearby. Don’t get under broken limbs that are hanging or caught in other branches overhead. And, unless you really know how to use one, leave chainsaw work to the professionals.

• Remove any broken branches still attached to the tree. Removing the jagged remains of smaller sized broken limbs is one common repair that property owners can make after a storm. If done properly, it will minimize the risk of decay agents entering the wound. Smaller branches should be pruned at the point where they join larger ones. Large branches that are broken should be cut back to the trunk or a main limb by an arborist. For smaller branches, undercut to lessen weight, remove branch, then remove stub.

• Repair torn bark. To improve the tree’s appearance and eliminate hiding places for insects, carefully use a chisel or sharp knife to smooth the ragged edges of wounds where bark has been torn away. Try not to expose any more of the cambium (greenish inner bark) than is necessary, as these fragile layers contain the tree’s food and water lifelines between roots and leaves.

• Resist the urge to over-prune. Don’t worry if the tree’s appearance isn’t perfect. With branches gone, your trees may look unbalanced or naked. You’ll be surprised at how fast they will grow new foliage and return to their natural beauty.

• Don’t top your trees! Untrained individuals may urge you to cut back all of the branches, on the mistaken assumption that reducing the length of branches will help avoid breakage in future storms. While storm damage may not always allow for ideal pruning cuts, professional arborists say that “topping” – cutting main branches back to stubs – is one of the worst things you can do for your trees. Stubs will tend to grow back a lot of weakly-attached branches that are even more likely to break when another storm strikes. Also, the tree will need all its resources to recover from the stress of storm damage. Topping the tree will reduce the amount of foliage, on which the tree depends for the food and nourishment needed for regrowth. A topped tree that has already sustained major storm damage is more likely to die than repair itself. At best, its recovery will be retarded, and it will almost never regain its original shape or beauty

Please note that this only includes some of the steps and information property owners should be aware of when managing storm damaged trees. For more information, including visual guides, please visit Oregon Department of Forestry : Urban forests : Forest benefits : State of Oregon

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