Sat Jan 24 14:50:00 UTC 2026: ### Trees Under Pressure: Extreme Cold Leads to Frost Cracks, Not Explosions
The Story:
As temperatures plummet across the United States, concerns have risen about the impact of extreme cold on trees. Contrary to some fears, trees do not literally explode in the winter, but the freezing and expansion of water within their vascular systems, the phloem and xylem, can lead to “frost cracks.” These vertical cracks in the trunk are caused by the rapid expansion and contraction of outer and inner bark layers, a phenomenon that creates snapping and crackling sounds, sometimes mistaken for explosions. While these cracks are generally not fatal, they can make trees more susceptible to decay, insect activity, and canker pathogens.
Key Points:
- Extreme cold can cause “frost cracks” in trees due to the freezing and expansion of water in their vascular systems.
- Frost cracks are vertical splits in the trunk, often occurring at previous weak points in the bark.
- Thin-barked trees, such as maples, lindens, and birches, are more prone to frost cracks.
- Non-native trees in areas with uncommonly low temperatures are also more susceptible.
- While frost cracks are usually not fatal, they can weaken the tree and make it more vulnerable to other problems.
- Minnesota trees are adapted to the cold, making frost cracks less of a concern in that region.
Key Takeaways:
- The term “exploding trees” is misleading; the actual phenomenon is frost cracking.
- Extreme cold poses a threat to trees, particularly those not adapted to such temperatures.
- Frost cracks can compromise a tree’s health, even if they are not immediately fatal.
- Regional adaptation plays a critical role in tree survival during winter.
- While the sound of cracking trees can be alarming, it is a natural response to extreme cold.
First Piper 