Frost Crack Damage Fact Sheet

Frost crack damage occurs when rapid changes in temperature cause the bark and underlying wood of a tree to split open. Frost crack damage typically occurs during winter months, when temperatures fluctuate dramatically between daytime warmth and nighttime cold. The process begins when the sun warms the bark, usually on south and southwest sides, causing it to expand. As temperatures plummet at night, the bark contracts rapidly, while the underlying wood contracts at a slower rate. This dissonance in contraction rates can lead to the formation of cracks in the bark and wood, known as frost cracks. Frost cracks can be up to several feet long and may heal in the summer only to reopen again in winter. Repetitive cracking and healing over the years can result in the formation of 'frost ribs'.

Causes of Frost Crack Damage

Several factors contribute to the formation of frost cracks in trees.

Temperature Fluctuations: Rapid changes in temperature, particularly when warm daytime temperatures give way to freezing nighttime temperatures, are the primary cause of frost crack damage.
Sun Exposure: Trees growing on the south or southwest side are more susceptible to frost cracks due to increased exposure to sunlight, which can cause rapid expansion of the bark.
Tree Species: Certain tree species, such as maple, ash, oak, linden, aspen, and fruit trees, are more prone to frost crack damage, due to variations in bark thickness, moisture content, and growth characteristics. Many fruit trees are very susceptible to frost crack.
Tree Age and Health: Older trees with thicker bark are more susceptible to frost crack damage, as are trees with compromised health or structural integrity.

Effects of Frost Crack Damage

Frost crack damage can have several adverse effects on trees, such weakened structural integrity which makes tree more susceptible to wind damage, insect infestations, and disease. The open wounds created by frost cracks provide entry points for pests, such as insects, and pathogens, like fungi, which can further damage the tree and hinder its ability to heal. Trees that experience recurrent frost crack damage may have shortened lifespans and reduced overall vigor, impacting their ecological value and contributions to the environment.

Management Options for Frost Crack Damage

While it may not be possible to completely prevent frost crack damage, employing certain management options can help mitigate its impact.

• Prune or remove any dead or damaged branches that pose a hazard or risk to people or property.
• Water and maintain adequate soil moisture levels, particularly during periods of drought or dry winter weather, to promote healthy bark and wood, and reduce the likelihood of frost crack formation.
• Avoid and minimize stress factors, such as compacted soil, improper planting depth, and mechanical damage, which can weaken trees and make them more vulnerable to frost crack damage.
• Avoid fertilizing late in the growing season and adding wood chips may avoid incidences of frost crack damage.
• Do not apply wood dressing as it will not seal exposed wood to moisture and pathogens.
• Regularly monitor the progress of the tree's healing process and provide ongoing care as needed, including appropriate irrigation, fertilization, and pest management.

Frost crack damage is a prevalent issue affecting trees during fluctuating winter temperatures. Unless frost cracks pose a hazard or risk to people or property where the removal of the damaged branch or trees is required, monitoring and proper maintenance should suffice.