Feb 03, 2015

The relationship between winds and trees is an interesting one. Although high and strong winds can reap destruction – as can all types of extreme weather – trees are biologically engineered to adjust to moderate winds which occur during the growing season. Wind loading is defined as a straight wind from one direction applied evenly over the stem, branches and tree leaves; wind release is what occurs when the stem and crown snap back into a normal position.

In any wind there are always gusts and calms which load and then release the tree alternately, and trees simply sway in the wind in normal conditions. Wind can actually help to strengthen the tree. In a hardwood tree, if a wind continues to come mainly from one direction all the time it will develop extra strength on the side of the tree towards the wind. In conifers, that strength is built up on the side of the tree opposite the wind. Over time, trees will develop something called wind firmness. The changing direction of winds across several years usually means most trees develop good wind firmness on several sides.

When winds hit stronger scales, such as in a storm, the situation changes and the threat of sizeable damage is significant. There are known to be six main types of storm damage to trees, as follows:


The tree is simply physically pushed over when the wind force is too great for the wood structure. The wood architecture may already have been damaged by past abuse, poor maintenance or pest problems, especially root rot.

Stem Failure

Old wounds don`t ever heal on trees. They may be grown over and sealed off, but those wounds are still present, which makes the tree structurally weaker. Constant wind loading and release causes damage.

Crown Twist

Tree crowns are the leaves, supporting twigs and branches and many of them have lopsided crowns. More wind loading on one side of the crown than on another produces a twist effect on major branches and the main stem and that twisting will magnify weaknesses around old injuries. The stem will split or branches collapse.

Root Failure

There are two types of tree roots: fine, absorbing roots and woody, structural roots. Absorbing roots have a large surface area, but are weak. Structural roots have a relatively small surface area, but are strong. Both provide anchorage for a tree but if roots are diseased or damaged by drought, excess water or construction, system strength may be compromised, causing the tree to fail.

Branch Failure

Wind always causes tree branches to stress. Usually, a tree can cope with this stress but heavy storms can expose vulnerable branches and snap or tear them. Generally the longer the branch, the more vulnerable it is to failure.


Trees are good conductors of electricity. Frequently, lightning can move in a line down the branches, stems and roots or wider along the entire tree cylinder. It destroys tree tissue by electrical disruption and heat.  Lightning struck trees can survive – if the soil is dry, water the tree and call an arborist as soon as possible.

Preventing wind damage can be challenge, which is where we at 404 CUT TREE, specialists in tree trimming, tree care and tree removal in Atlanta, can assist. Trees can`t be completely protected from wind and storm damage unless fully enclosed. But damage can be minimized.   404 CUT TREE has special expertise in performing pre-storm assessments, tree removal in The Metro Atlanta Area and tree removal in Marietta. A small amount of pre-storm trimming can reduce risk of storm damage.

Be aware that after heavy winds some trees may appear structurally safe but damage might still have taken place. Don`t just look at the stem and the branches for problems; inspect the roots too for evidence of disruption. An arborist is trained to perform root plate assessments.

Call 404 CUT TREE to discuss pre-storm assessments, tree care and health of your trees in the Metro Atlanta Area.