As we move into storm season for north Georgia and the metro Atlanta area, it becomes even more important to understand why trees sometimes topple. Falling trees can pose a threat to nearby homes, businesses, and other structures, as well as to people living and working in the vicinity. In general, trees are more stable when they have healthy root systems, proper soil conditions, and well-trimmed crowns.
Depending on its species, a tree may require roots to spread out quite a bit farther in every direction than the branches do. Trees in urban areas are often restricted to smaller areas, which can prevent them from developing root systems extensive enough to support their growth above ground. In addition, existing roots can be damaged by digging and development, which can weaken them and put them at risk of root rot and other infections. Infected or decaying root systems are difficult to spot unless a fungal infection starts to sprout mushrooms or other visible fungal growth at or near the bottom of the tree. Potential root problems can be tested by an arborist, who will take samples to examine for decay and disease-causing organisms.
Even trees with well-developed and healthy root systems can become unstable when the soil in which they grow becomes saturated. Soil saturation often occurs during and after heavy or long-lasting rains, especially if the area does not have good drainage. If your yard has enough Georgia clay to slow or stop rainwater from draining away, or if parts of your yard sometimes flood during storms, keep an eye out for trees that are starting to tilt or lean in one direction.
Wind is also a factor in falls. Whether it’s part of a storm or just a breezy day, high winds can break off branches or simply lever a tree right out of the ground. The higher your trees grow the more leverage the wind will have. Trees with compromised bases (either from root decay or watery soil) are much more easily blown over, as are trees with heavy crowns. Sometimes trees are exposed to higher winds after nearby trees or structures are removed, so newly-cleared land or yards that have recently had several trees removed should be monitored for potentially unstable trees.
General signs of an upcoming fall include:
- Leaning or tilting
- Cracks in the trunk, especially near the base
- Fungi growing near the base of the tree
- Unhealthy foliage resulting from unhealthy roots
- Unusually wet soil or minor flooding around the tree
- Damage to the base or roots from yard work, trench-building, or construction
If you are concerned about your trees, consult an arborist to assess the tree and discuss your options for stabilizing or removing it.