Violent storms can wreak havoc on trees. Heavy snows, strong winds and flooding can all create significant injury at different points in tree development. Young trees can be uprooted or hopelessly broken. Older trees can become cracked or lose weak limbs. Water damage can infuse roots with salt or contaminants. Some storm damage of trees can be prevented with bracing, staking or other measures of support. A careful assessment of your landscape trees in advance of storm season can help prevent losses.
Some species or cultivars of trees and shrubs are injured if temperatures fall below a minimum tolerance level. Frost cracks, sometimes called freeze cracks, appear as shallow to deep longitudinal cracks in the trunk of trees. They are most evident in winter at temperatures below 15°F. Frost cracks occur on the south or southwest sides of trees because this area experiences the greatest temperature fluctuations between day and night. A sudden drop in temperature causes the outer layer of wood to contract more rapidly than the inner layer, which results in a long vertical crack at weak points in the trunk. Once a freeze crack occurs on a tree, it is likely to appear annually. Trees most susceptible to frost cracks include London plane, oak, Norway and red maple, horsechestnut, crabapple, walnut, linden, and willow.