Cover young trees if frost is expected. Avoid planting in low lying areas subject to frost. Do not use high nitrogen fertilizer late in the growing season. Frost Crack Long vertical bulges or cracks on trunks indicate a recurring stress. Cracks or seams start at wounds or branch stubs.
Serious damage can result from seemingly minor wounds.
A sudden, sharp drop in winter temperature causes the outer layer of wood to contract more rapidly than the inner layer, which can result in a long vertical crack at weak points in the trunk. Depending on the tree species, the tissues at the margins of the injury may grow so rapidly that they curl in on themselves, preventing complete closure of a wound. Avoid wounds to the trunk and properly prune branches to prevent the formation of frost cracks. This is caused by inadequate soil moisture during extended periods of abnormally low rainfall. Symptoms include wilting, off-color foliage, twig and branch dieback in the crown, and the death of fine roots.