Every year, deciduous or deciduous trees renew all their leaves, losing their foliage when autumn arrives. The reason is that in this season the hours of light are reduced, the solar radiation loses strength and the soils often freeze, making it difficult for the roots to capture water and nutrients. Under these conditions, the productivity of the leaves decreases. When maintaining foliage costs more than it produces, the most profitable strategy for the tree is to lose the leaf and spend the unfavorable season in a state of low activity or rest. At this point the supply of sap (and chlorophyll) is withdrawn creating a film between the branch and the base of the leaf, which is left to its fate. The wind and the rain make it fall.
Why do the leaves fall in autumn?
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