In a few months when you’re curled up inside your house as the snow comes down outside, you may look out your window a wonder how your tree survives such harsh weather. Well, the truth is that trees have a lengthy preparation process one that can start as early as late August.
Winter trees are in a state known as Dormancy, similar to hibernation. In this state the metabolism, energy consumption, and growth is slowed. In the paragraphs below, we will discuss the process a deciduous tree goes through to prepare itself for dormancy.
Step 1: Conserving Energy
The first step in preparing for dormancy is to limit the energy needed to survive. Trees do this by releasing a chemical called ABA (Abscisic acid). ABA has two main purposes suspending growth and cell division, and shedding leaves. Since trees do not make food in the winter they have no use for leaf mass that requires energy to maintain. When ABA builds up at the leaf’s stem it signals the leaf to break off.
Despite common belief, the chemical ABA does not change leaf colors. The change in color comes from antioxidants formed from trapped glucose, tannin – a bitter waste product, and the lack of chlorophyll which allows colors that were in the leaf all along to show.
Step 2: Preventing Freezing
The biggest problem trees face is keeping the water in their cells from freezing. Trees combat this problem in 3 ways.
1) Make their cell membranes pliable; this allows water to move out of the cells and into the spaces in between. This keeps the frozen water from bursting the cells.
2) Create a tree version of anti-freeze. In fall, trees pump natural sugars through their systems which lower the freezing point inside their cells.
3) The first and second ways of achieving this trigger the third way. In this process, the water left in the cells becomes so thick that it is almost a solid, which allows the tree cells to avoid crystallizing.
Trees colorful leaves may get the most of your attention during fall. However, don’t forget what an intricate preparation process your tree is going through this season. Better yet, help out your tree by making sure they are properly watered, aren’t battling insects, and are at their best health. Our arborists recommend Fall bio-stimulants as the best way to make sure your tree is prepared for this process and their long winter’s nap.
