Frost Cracks: What They Are & What To Do About Them

Below freezing temperatures can take a toll on anyone. Chapped lips, dry skin, frozen noses – winter is not always sledding and snowball fights!

And just like cold weather can affect us, it can create changes in nature as well. You may have noticed that some of your trees now have vertical splits down their trunks. Or maybe you haven’t ventured outside to look at your trees yet, but you’ve heard large cracking sounds coming from your yard. These noises are so loud and sudden that they’ve been compared to a rifle shot!

As unlikely as it may seem, these two things are related, and are called frost cracks. During the colder months, the sun shining directly on the tree during the day warms the outside of the tree, especially on the south and west sides. A sudden drop in temperature (usually at night) causes the bark to shrink, while the inside of the tree takes longer to cool down and contract. As a result, the bark rips and the wood below it splits – making a loud cracking sound as it happens.

Trees Impacted by Frost Cracks

Trees with thinner and lighter bark are more susceptible to frost cracking.

In our area, those include the following:

• apple
• beech
• crabapple
• elm
• goldenrain tree
• horse chestnut
• linden
• London plane
• maple
• oak
• walnut
• willow

Dealing With Frost Cracks

So if you’ve noticed one or more of these vertical cracks on your trees, what do you do?

Most often, the tree will heal itself. As the weather warms, the tree will try to grow over the crack with wood called “reaction wood.”

The crack has injured the tree however, and makes it more susceptible to fungi and insects, so be diligent with pruning, watering, and other tree care plans to ensure that your tree maintains its health.

The frost crack might open up again each winter, so be sure to inspect your tree each spring.

If you have any concerns, give us a call – we’re happy to take a look at your trees to see if they need any special treatment.