Evergreen trees

[sabrinah]

What makes evergreen treees evergreen? Can they only exist in certain environments?

[Peter R]

Evergreen trees do not have the inbuilt system other plants have that make them loose their leaves in Winter. When the leaves go red, diciduous (non-evergreen) plants are sucking all the sugars and other stuff out of the leaves, to save energy. This allows them to grow back after winter. Here in Australia, winter is not too cold for the plants, so most plants just "tough it out" for the winter, because there is enough sun to give them the energy they need.