Unraveling the Mystery of 'Exploding Trees': A Winter Phenomenon Explained
As winter's icy grip tightens across the United States, a peculiar phenomenon has captured the attention of social media and meteorologists alike: the so-called 'exploding trees'. But what exactly are these 'exploding trees', and are they as dramatic as their name suggests? Let's delve into the fascinating science behind this winter wonder.
John Seiler, a professor and tree physiology specialist at Virginia Tech, encountered a unique sight during his morning stroll with students. A sweet cherry tree bore a jagged scar along its trunk, prompting Seiler to recognize it as a result of a 'tree explosion'. However, Seiler clarifies that this term is a bit of a misnomer.
The phenomenon, scientifically known as 'frost cracks', occurs when temperatures drop rapidly or trees fail to adjust to the cold, causing the sap or water inside to freeze. As this frozen water expands, it exerts immense pressure on the bark and wood, leading to cracks or splits. These splits can produce a loud bang, often likened to an explosion, but it's more accurately described as a gunshot-like sound.
Seiler explains, 'It's like when you rush to get a cold Coke from the freezer and forget about it, only to find the can has split open. That's what happens to the tree.'
While 'exploding trees' might sound alarming, they are not inherently dangerous. According to the National Forest Foundation, there are numerous historical and current observations of trees 'exploding' due to extreme cold. However, these events typically don't pose a threat to passersby or the tree itself.
Seiler reassures, 'It's loud, but not dangerous. The wood doesn't fly through the area, and the tree's split opening doesn't kill it. However, it can be vulnerable to insects or infections from fungi or bacteria.'
Doug Aubrey, a professor at the University of Georgia's Warnell School of Forestry and Natural Resources, adds that the fate of a tree during a 'frost crack' depends on the species. If the bottom of a stem freezes, the entire tree might die, but many trees can regenerate from underground buds. Freezing in a branch may lead to the death of that branch but not the entire tree.
During winter storms, Aubrey warns of a more significant risk: heavy branches falling due to ice or snow accumulation. These falling branches can cause damage to homes, vehicles, or even people. The size of the tree plays a crucial role in the potential impact, with larger trees having more large branches and leaf area.
Seiler agrees, emphasizing that heavy ice and wet snow accumulation on trees are more concerning, as they can cause branches to fall or the tree's top to snap. He advises, 'Stay clear of heavy ice accumulation and wet snow, as a falling branch could be extremely dangerous.'
In summary, while 'exploding trees' may sound dramatic, they are a natural winter occurrence caused by frost cracks. Understanding the science behind this phenomenon helps us appreciate the resilience of trees and the potential risks associated with winter storms.
