During the summer, with the long hours of sun and the right amount of liquid water, trees are busy growing while storing and making food. But what about the winter season? The days are way shorter, and water is difficult to get. Deciduous trees prepare for winter in several different ways. As trees grow, they discard older leaves and produce new ones. This is crucial since the leaves get destroyed over time by weather, disease, and insects. The shedding and replacement go on all the time. Additionally, deciduous trees, such as elms, maples, and oaks shed all their leaves in the autumn to prepare for winter. Evergreens retain most of their leaves in the winter. They have distinctive leaves, resistant to moisture loss and cold. If you need some help with your tree maintenance, contact a York tree specialist. Some, including fir and pine trees, have thin, long needles. Some, such as holly, have wide leaves with waxy, tough surfaces. On dry, cold days, these leaves might curl up to lessen their uncovered surface. Evergreens may keep on photosynthesizing in the winter as long as they get the right amount of water. However, the reactions happen more slowly in colder temps. In the Summer During the summer, leaves produce more glucose than the trees need for growth and energy. The excess is converted into starch and stowed until needed. As the daytime grows shorter in the fall, trees begin to close their food production. Many changes happen with a deciduous tree’s leaves before they fall from the branch. The leaves have mostly been preparing for fall since it begins to grow in the springtime. At the bottom of every leaf is a unique layer of cells referred to as the separation layer or the "abscission.” All summer long, tiny tubes which go through this layer transport water into the leaf and food back to the tree. In the autumn, the cells of the abscission layer start to swell and create a cork-like material, diminishing and ultimately shutting off flow between the tree and the leaves. Waste products and glucose are stuck in the leaf. Without fresh water to rejuvenate it, chlorophyll starts to disappear. Comments are closed.
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