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Some trees move their stored "food" nutrients below ground to their roots, and lose their
leaves. These are called deciduous trees.
An example is the sugar maple tree.
Other trees have needles like Christmas trees. These are called evergreen trees. The evergreen
trees continue to use sunlight and carbon dioxide in the air to make food during the winter.
The needle-like leaves are adapted for the cold temperatures and dry conditions of winter.
The deciduous trees will wait until spring, longer days and then the sap will rise again and
leaves will grow and make more food and oxygen (photosynthesis) again.
Anthony Brach, Ph.D
Deciduous' in winter, become dormant during the winter. That means that growth and most
cellular activity stop during cold
weather. Leaf and flower buds are formed before frost that will begin growth again in the
spring Sugars and other material in the cells of the buds and other living tissues keep
them from freezing solid and being harmed. During the growing season the tree stores sugar
so that there is a food supply to start growth in the buds again in the spring - that is the
sugar that people "tap" to make maple syrup in the spring.
Photosynthesis and respiration slow down in winter in evergreen trees, but do not stop
completely. The needles of evergreens have much smaller surface area and fewer pores
than broad leaf deciduous trees, so they do not lose much water in winter. Because of
cold, not much water is available to the trees in winter.
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