Why do evergreen stay green all year round?
Many trees do not take a winter rest but continue to have green leaves all year round. We call these trees “evergreen.”
On of the great dangers a tree faces in the winter is that of losing precious water.
Trees absorb water through their roots absorb little or no water. And so, if the tree kept losing water through its leaves, the tree would dry out and it would die.
Many trees with broad leaves which lose more water, such as elms and maples, drop their leaves in winter.
Many evergreens, such as pines and firs, have tough, needle-shaped leaves that slow the loss of water. They can withstand frost and drying winds.
Keeping their leave enables evergreens to manufacture food all year long, and to keep their green color.
This is one reason why the forests of the far north are mostly evergreens.
But evergreens do not keep the same leaves all their lives. They shed old leaves a few at a time throughout the year.