They dont, you must be mistaken.
No not really - most tropical rainforest trees are evergreens and keep their color until the leaves fall off. Certain palm trees do not change color until they die, or fall off too. Eventually yes, but Conifers have smaller leaves so they change slower.
Deciduous trees change the color of their leaves before they fall off in autumn.
Evergreen trees do not change color in fall and winter because they do not lose chlorophyll due to evaporation. The needles are covered in an oily substance preventing the loss of chlorophyll and shielding it against frost.
Evergreen trees also loose their leaves one by one. Since all the leaves do not fall at the same time we do not notice this kind of leaf fall.
The evergreen.
No. I do not know of any Maple species that are Evergreen.
Evergreen trees do not shed their leaves in the Autumn.
no the willow tree is one of the coniferous trees used as Christmas trees.
Unlike, other pine trees, their needles actually don't fall off! :)
Deciduous trees often don't shed their leaves in autumn if they are grown in warm or temperate climates. Evergreen trees retain thier leaves throughout the year.
Deciduous trees change the color of their leaves before they fall off in autumn.
Evergreen trees lose only a few old leaves at a time.