Frost cracks on tree trunks show up as a sudden vertical split, usually on the south or southwest side, and they catch a lot of Frankfort, KY homeowners off guard the first time they see one.
What Causes Frost Cracks on Trees in Frankfort, KY?
Frost cracks form when a sunny winter day heats bark on the south or southwest side of the trunk several degrees above the air temperature, then a clear, fast-cooling night snaps that side back down — the sudden contraction splits the bark and outer wood in a straight vertical line.
The pattern repeats through the coldest stretch of the year, which is why Frankfort’s swings between sunny days and hard-freeze nights in December and January produce more of these than a steadily cold winter would. The University of Kentucky Cooperative Extension Forestry program lists frost cracking (sometimes called “southwest injury”) as one of the more common winter bark injuries on landscape trees in this part of the state.
Which Trees Are Most at Risk?
Thin-barked, fast-growing species take the brunt of it: maple, honey locust, linden, crabapple, and other ornamental fruit trees. Age matters as much as species — a tree still within its first two or three years after planting has thinner, less-shaded bark than a mature specimen and is far more likely to crack. A tree that already has root or trunk stress from construction, mowing damage, or drought is also a more likely candidate.
Protecting at-risk trees before the cold sets in is straightforward: a light-colored trunk wrap or plastic guard on the south/southwest side, applied in fall and removed in spring so the bark can breathe. Materials alone typically run $15–$40 per tree if you wrap trees yourself; having Frankfort Tree Pros install trunk guards as part of a fall visit typically runs $50–$120 per tree depending on trunk size and site access — a typical range, not a quote.
Common Questions
Will a frost crack kill my tree?
Usually not by itself. Most trees seal a frost crack with callus tissue over a season or two, though the wound can invite decay or insects if the tree is already stressed.
Can a frost-cracked tree be repaired?
There is no way to “heal” the crack directly. The best move is removing torn bark edges cleanly and watching the tree; wrapping trunks the following winter prevents new cracks.
Do all trees get frost cracks?
No — thick-barked species like oak and hickory rarely crack. Thin-barked trees such as maple, honey locust, linden, crabapple, and other fruit trees are the ones at real risk.
Related: Tree Planting & Species Selection | Root Damage Repair | Tree Disease & Pest Diagnosis
Not sure if a crack on your tree is cosmetic or serious? Get a free estimate or call or text (859) 310-1209.
Source: University of Kentucky Cooperative Extension Forestry.
Last updated: September 9, 2026