PATHOLOGY

Detailed explanation-1: -In autumn, with the cooler temperatures and shorter days, the production of one hormone called auxin reduces. This in turn puts a strain on the abscission layer and causes the bond between leaf and branch to weaken. Eventually, the strength of the join is weakened enough that the wind will blow the leaf away.

Detailed explanation-2: -Winter temperatures cause the production of auxin to slow down and this breaks the abscission layer, causing the leaves to detach from the trees. Losing leaves helps the tree to retain water during in the winter and means that it needs less energy to stay alive. The fallen leaves help to add nutrients to the soil.

Detailed explanation-3: -Tree leaves will start falling either early or late October – about a week after peak color.