Why do trees shed their leaves?
Trees that lose their leaves in winter are called deciduous while those who don`t are called ever green. Common deciduous trees in the North hemisphere are species of ash, aspen, beech, birch, cherry, elm, hickory, hornbeam, maple, oak, popular and willow. In tropical and subtropical areas the most common are several species of acacia, baobab, roble, ceiba, chaca and guanacaste.
Sofia – Nasia – Kostas – George.
In warm weather the tree loses a lot of water through little holes in leaves. In winter, there is not enough water to replace the water it would lose through the leaves. If the tree did not seal the spots where the leaves grow, it would die. So, as the water cannot flow in and out of leaves, they change colour and fall. When spring comes, new leaves will sprout and grow again.
Dina – Joanna – Laoura – Diogenes – Ariel.
If the tree did not lose leaves, the watery sap inside would freeze, causing the tree to die. So it gets rid of the leaves to save heat and water. It can live without leaves for a while, until warm weather comes again.
In a way, trees become dormant, like some animals, so as not to die during cold or dry weather. It`s a strategy to survive.
Ever green trees have needles instead of leaves, which are water resistant, so they don`t drop them - except oak trees which keep their broad leaves and tamarack trees which shed their needles.
Didi – John – Zacharias – Johnny.
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