Take an active role in determining the fate of your trees. Recognizing warning signs may help you extend the life of these structural garden elements.
As an arborist, I’m trained to have a discerning eye. While most people drive up to a stop sign and look to the left and to the right, I look left, right, and up. I avoid some intersections because I know what’s growing on the corner—a tree with a structural defect that needs only a strong wind or an ice storm to send it crashing to the ground. Though tree defects are easy to spot if you know what to look for, the untrained eye may have a hard time recognizing the signs of a tree in serious trouble.
Structural defects occur in trees for a number of reasons, and even though a tree may be structurally compromised, it could live on for years. One example is a tree with a hollowed-out trunk. Since fluids are conducted upward in the outer rings of wood and downward in the tissue just inside the bark, a tree can be big and green yet be mostly hollow. Physiologically, this tree is still functioning, but it may not be structurally sound. One stiff wind could send it toppling.
Sometimes solving the problem a hazardous tree may pose is as simple as moving the target that makes it a hazard. For example, if a limb is in danger of splitting from a trunk and falling on the picnic table below, moving the picnic table or cabling the limb may mitigate the hazard. In other cases, a health-care program designed to increase a tree’s vigor may help it overcome minor root damage or the stress caused by insect or disease damage.