Following our tropical storm, many landowners saw damage to trees in forests. We asked Dr. Moorhead to discuss this with us at this year’s Forestry & Wildlife program. At our first stop, we looked at damaged longleaf, and Dr. Moorhead gave an overview of assessing this damage. This is an exert from the publication “How to Evaluate and Manage Storm-Damaged Forest Areas“.
Storms ultimately cause damage by uprooting, wounding, bending, and breaking trees. Standing water following a hurricane can cause additional stress on trees and kill them. It’s good to have a plan to manage damaged timber.
- Step 1 – Sketch or get aerial photograph of area ASAP.
- Step 2 – Ground check damage to determine the need for salvage. This depends on location, amount of salvage and management objectives.
Type of Damage
Breakage
This is the most common form of damage. In pine trees, this lowers the value since breakage is random and trees are cut to specific links. Hardwood trees are seldom killed by breakage. Breakage also permits entry of stain and decay fungi.
Recommendations: For pines, if 3 live limbs or less remain, the trees should be harvest as quickly as practical. For hardwoods, trees with broken tops or branches over 3 inches in diameter should be salvaged during next scheduled harvest.
Twisted Trunks
Logs from trees that have this damage may fall apart when sawn for lumber. Those pines may have pitch flow along the truck, but appear normal.
Recommendations: Trees with evidence of twist injury should be removed, since the problem will not disappear with time.
Root Damage
Get them out! These have to be salvaged quickly since stains, decays, secondary insects (Ips, powderpost, and ambrosia beetles) will further hurt the tree. Root-sprung pines will not die quickly, but will eventually incur invasions from blue stain fungi and bark beetles.
Major Wounds
This can occur from falling tops, other uprooted trees, and branch breakage. Pine trees with major wounds to the lower bole and large roots may be attacked by bark beetles. In hardwoods, woulds that do not penetrate more than 2 inches deep (into sapwood) and have less than 144 sq inches of surface area will have only localized stain, but little decay.
Recommendations: Trees with major wounds should pretty much be removed during next schedule harvest, or included in salvage operation.
Bent Trees
This is much of what we observed at our program Tuesday. Pine trees bent to the extent that cracks and resin flow occurs could be invaded by bark beetles and disease-causing organisms. Hardwoods are not usually attacked by insects or disease.
Recommendations: Trees under 15 feet in height usually straighten. Taller, more bent hardwoods need to be removed during salvage or next scheduled harvest. Many large, green, standing trees may not be usable for veneer poles or lumber since internal ring shake, splintering and separation of the wood fibers. Many times, the only external evidence of this damage is pitch or sap flow were the injury has broken the bark. It’s easy to overlook these signs.
Below is a table of choices for storm-damaged trees.