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Why is it important for the plant that the leaves change color and then fall off the tree during the fall?
Question Date: 2013-03-18
Answer 1:

Actually, not all plants and trees lose their leaves during the fall. Some types of trees, such as evergreen trees, will lose a few of their pine needles at a time all through the year. This makes them appear green all year long! Trees that do lose their leaves in the fall are called “deciduous trees” (deh-sid-you- us). Deciduous trees lose their leaves in the fall because it is more difficult for the tree to survive in the winter. Trees need sunlight to grow, and there is less sunlight in the winter so it is harder for the tree to make enough energy to keep all those leaves alive. To save energy, the trees lose their leaves and become “dormant” (asleep). The tree is still alive, and survives off energy provided by the roots and energy the tree has stored up over the summer (sort of like a hibernating bear). When the weather improves and there is more sunlight, the tree has enough energy to grow back its leaves. During the spring and summer these leaves grow and make energy for the tree that it will store again the next fall.

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