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.
In respect to this, why do some trees lose their leaves early?
Too much or too little water can cause late summer leaf loss. In drought-like conditions, thirsty trees will drop leaves to combat drought stress. Similarly, over-watered tree leaves can turn yellow and fall off. Too much water can suffocate tree roots, which causes stress in the canopy.
Why are maple tree leaves dropping early?
Trees drop their leaves early for a variety of reasons. Leaves that have been infested with insects or diseases will, often, drop early. The maple in my yard has disease tar spot, which is causing the leaves to drop now. Pests like scales, mites and white flies can also cause early defoliation.