Why do leaves fall in autumn?

Leaves fall off deciduous trees because the leaves have stored food for the trunk of the tree in winter. A couple of reasons are: in cold and dry weather the leaves get, damaged, in autumn and winter the leaves can’t convert sunshine into energy. Also, deciduous trees lose their leaves because to not lose water they close off the little holes that hold the leaves

Why do Evergreen trees not lose their leaves?

Evergreen trees can absorb light and water they have enough energy to store both, the leaves have a wax layer that helps them survive.