Why Do Leaves Fall off Trees?

Answer

Leaves fall off trees as part of the usual mechanism of trees. At the base of each leaf there is a special layer called the abscission zone and when the time comes to shed a leaf, the cells in this layer start to swell thus slowing the carry of nutrients between the tree and leaf. Immediately the abscission zone is blocked, a tear line shapes and moves downwards, until finally the leaf is blown away or falls off.
2 Additional Answers
Ask.com Answer for: why do leaves fall off trees
In early autumn, the veins that carry fluids to the leaves close off. A layer of cells severs the tissue that support the leaves and caps off the end of the branch. The leaves gradually fall off.
Not all plants lose their leaves. Conifers remain green and keep their leaves for two to four years.
During winter the air is cold and dry. Rather than have a tree's water supply absorbed by the dry breeze, the water is transferred into the limbs and truck of the tree and the leaves then dry up. Once dry, they fall off until Spring when the weather warms and new leaves sprout.
Q&A Related to "Why Do Leaves Fall off Trees"
Provide a healthy growing environment. Orange trees need full and direct sunlight throughout the day and regular watering. Keep the soil irrigated and ensure that it drains well to
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The falling of leaves depends on the environmental factors and the genome of the tree. Most trees such as the deciduous trees, lose their leaves to conserve moisture and energy over
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Probably elm blight.
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Trees do not have enough light or water for photosynthesis. They
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Leave plays important role of Photosynthesis for a plant. When a leave becomes old, its capacity to make food gets lowered. So old leaves fall off trees. ...
The falling of leaves depends on the environmental factors and the genome of the tree. Most trees such as the deciduous trees, lose their leaves to conserve moisture ...
The falling of leaves depends on the environmental factors and the genome of the tree. Most trees such as the deciduous trees, lose their leaves to conserve moisture ...
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