How Do Trees Handle The Winter Cold?

Winters in Cambridge are cold and snowy, and they can last for months. Animals handle the weather by packing on the pounds before holing up in a den and hibernating or spending most of their days in shelters that protect them from the elements. Many birds head south.

Trees don’t have the same luxury as people and animals. They are rooted in place all winter long. Deciduous trees shed weight, rather than adding it. Most conifers maintain their needles (the larch, or tamarack, is one notable exception). They can’t turn up the heat or seek shelter. They’re exposed to whatever Mother Nature throws their way. So, how do trees manage the cold, and can tree trimming help them survive?

Adapting to the Climate

Like much of life on this planet, trees contain a lot of water. You may be surprised to find out that their structures are approximately 50% water. Water freezes at 0 degrees Celsius, so it’s a bit shocking to find out that trees don’t freeze to death in the winter.

Trees are adapted to the climates they grow in. Structurally, the bark on a tree provides it with a layer of insulation from the cold. The tree’s roots, vital for its survival, are buried below the surface. Though the upper layers of the ground may freeze, the deeper layers generally remain above freezing. In addition to these traits, trees go through preparations every year to get ready for the winter.

Preparing for the Winter

While trees can’t add layers of fat or clothing to protect them from the upcoming winter, they do take steps to prepare them for the cold. The preparations begin as daylight length shortens in late summer. The biggest changes are hidden from view. You won’t notice anything different until autumn rolls around when the leaves on deciduous trees begin changing colour and dropping to the ground.

Surviving the Cold

If all the water in the tree froze, it would never survive because much of the water is held in the tree’s live cells. So, the tree adjusts to keep that from happening. From what scientists currently understand, trees undergo three processes that help them survive:

1. Water migration: The membranes of living cells become more pliable, allowing for water migration to occur. The water moves from inside the cell out, occupying the spaces in between cells. In the cold, the cells shrink, making room for the water and reducing the pressure on cell walls.
2. Starch conversion: The next step in the process is to convert the starches in the tree into sugars. After the water migrates out of the cells, the liquids that remain become sugar concentrates. The sugar has an antifreeze effect that reduces the cell’s freezing point. The water outside the cells freezes, but the cells themselves don’t.
3. Liquid suspension: In the final step, the sugary liquid inside the cells turns viscous. The level of viscosity is so high that the liquid appears solid. It’s similar to the way silica appears to be solid— though it’s really still a liquid — when it’s supercooled to make glass. This process prevents the liquid from crystalizing, which would damage or destroy the cells.

Tree preparation and adaptations allow the tree to go dormant and survive winter without freezing to death. The dead cells die, but they’re already dead, so the freezing temperatures can’t hurt them. Most of the trees’ structure is composed of dead cells, so taking the steps to protect the living cells allows trees to handle tough winter conditions.

Tree Trimming Services for your Trees

Martin’s Tree Service offers winter tree service in Cambridge. Tree trimming in the winter helps your trees get ready for the spring growing season while they are dormant and have time to heal. Winter pruning also eliminates the hazards of dead or weak branches. Trust the experts to care for your trees and keep them healthy all winter long. Contact us today for a free consultation.