Trees Have Unique Ways Of Handling Winter Cold

Trees are made of ½ water, a less amount in winter. If the temp drops low enough, the water in even the most adaptable tree will freeze.

So how do trees endure below-freezing temps? They can’t move south or produce heat like a mammal. The below-ground parts of a tree are insulated by a layer of snow. This is vital to winter survival. However, the exposed parts of a tree aren’t so protected.

Do Trees Have Unique Ways of Handling Winter Cold?

To endure winter cold, a tree starts its preparations in late summer as days get shorter. Cold acclimation happens slowly and includes many physical changes in stems, roots, and leaves. And while fall colors get all the attention, it’s what trees do later in the fall that is the most stunning and is difficult to see.

Ways Trees Stop Freezing

Arborists suggest three ways in which trees prevent freezing. One is to alter their membranes during the cold weather so that the membranes get more flexible. This lets water migrate out of the tree cells and into the areas between the cells. The relocated water applies pressure against the cell walls, but this pressure is counterbalance as cells shrink and take up less space.

The second way a tree keeps from freezing is to sweeten the fluids in the living cells. Come autumn, a tree changes starch to sugars, acting as an antifreeze. The fluid in the living cells get stronger with these natural sugars and reduces the freezing point in the cells. Because the cell membranes are more bendable in winter, they’re squeezed by the enlarging ice crystals.

The third way is where the liquid cell contents get so thick that they appear to be solid, a sort of molecular suspended animation that imitates the way silica stays liquid as it is cooled into glass. This third mechanism is set off by the progressive cellular dehydration that stems from the first two ways and allows the supercooled contents of the tree’s cells do not crystallize.

All three techniques are intended to stop living cells from freezing. That’s the key for the tree; don’t let living cells freeze.

If you are concerned about your trees handing the winter weather, one of our arborists will be more than happy to consult with you on the health of your trees.

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