Why Trees Lose Leaves - MR. GLINES GRADE 4 HUDSON, MA

MR. GLINES GRADE 4 HUDSON, MA

In tropical and subtropical forests, trees shed their leaves at the onset of the dry season. Many types of trees shed their leaves as a strategy to survive harsh weather conditions. Trees that lose all of their leaves for part of the year are known as deciduous trees. Those that don't are called evergreen trees Since deciduous plants lose their leaves to conserve water or to better survive winter weather condi leaves must fall. Evergreens can hang on to their leaves through winter, because their foliage is coated in a wax that helps protect against cold, and their cells bear anti-freeze chemicals that ward off winter's worst woes. Not so for broadleaf, or deciduous, trees.tions, they must In tropical and subtropical forests, trees shed their leaves at the onset of the dry season. Many types of trees shed their leaves as a strategy to survive harsh weather conditions. Trees that lose all of their leaves for part of the year are known as deciduous trees. Those that don't are called evergreen trees.regrow new foliage during the next suitable growing season Deciduous trees and shrubs lose their leaves in the fall as a protective measure. Their leaves are tender, and cold temperatures would kill them. Cold weather is not the only reason why trees lose leaves. Another function of leaves is transpiration: water evaporating from leaf surfaces draws water and nutrients into the base of the tree through the roots, via capillary action. But in hot, dry weather transpiration is a threat because there may not be enough water to replace that which is lost. Hence some species are "drought deciduous," dropping leaves in dry weather, becoming dormant until conditions improve As the days get cooler and frost is in the air, deciduous trees and shrubs put on an autumn show in all shades of red, yellow, purple, and brown. The splendor of crisp fall days and vibrant leaves brings to mind memories for nearly everyone who lives in an area where deciduous forests are the dominant vegetation. In many parts of the country, autumn leaves are an important factor in tourism. Many think that cool weather or frost cause the leaves to change color. While temperature may dictate the color and its intensity, it is only one of many environmental factors that play a part in painting deciduous woodlands in glorious fall colors. Trees that lose their leaves in the winter are called deciduous trees. They lose their leaves to conserve moisture and reduce the amount of energy they must consume in order to stay alive. The leaves of some deciduous trees turn bright colors before they drop to the ground, while others simply fade or turn brown. Environmental factors and the genome of the tree affect how quickly the leaves fall. KD
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