Frost cracking occurs when the tree bark separates from the wood. Interestingly, frost cracks are not caused by frost, but due to the tree wood drying and shrinking. This creates splits and openings in the tree, some big enough for a hand to fit through. Unfortunately this also makes the tree more susceptible to cankers and fungus issues. Trees with openings leave the tree vulnerable to pathogens and other unwelcome guests. So why does frost cracking occur?
When trees are exposed to freezing temperatures the water in the tree’s cells also freeze and the cells shrink. The tree trunk attempts to shrink also, but the temperature is actually much higher in the center of the tree. This causes a great strain in the layers of wood that can only be released by a separation of layers or “crack”. When the cracking occurs the sound may be as loud as a rifle shot.
As temperatures decrease, the likelihood of frost cracking increases. The sub-zero temperatures our area faced this year has increased the chances of trees developing frost cracks. There are many area villages monitoring trees with frost cracks that developed after the recent “polar vortex” weather conditions. There are a number of factors that affect the probability of tree frost cracking. Trees in exposed conditions, such as in a landscape are more susceptible than trees in wooded areas. Placement in the landscape can also affect frost cracking. Cracks typically appear on the south or west sides of a tree, due to sun exposure and uneven tree heating and cooling. Trees that are smaller in trunk diameter (6-10 inches) are also more likely to develop frost cracks, because of a higher water percentage in a younger tree’s cells. In addition, certain tree species are more vulnerable to frost cracking than others. Crabapple, Ash, Beech, Horsechestnut, Sycamore and Linden trees are just a few examples of tree types that are more likely to suffer from frost cracking.
To determine the extent of damage, a tree believed to be suffering from frost cracking should be examined by a Certified Arborist. An Arborist can recommend options and solutions with the tree’s health in mind. Have a tree suffering from frost cracking? Call us today to have a KTS Certified Arborist inspect your tree.