Most trees are green during spring and summer. In fall, the leaves turn colors. Then they drop off. But certain trees, like pines and spruces, stay green all year round.
The leaves that change color and drop off do so for good reason, reports 3-2-1 Contact magazine. These kinds of leaves are not built to stand up to icy winds and freezing cold temperatures. In self-defense, the tree's leaves change color, dry out and die. Once the harsh winter is over, the tree grows a complete new set of leaves.Evergreens, however, are designed to stand up to severe weather. Their waxy, needlelike leaves hold their water and so do not dry out. These sturdy little leaves can also survive blasts of winter winds.
Most evergreens keep their leaves all year round. Many of them keep their leaves for several years. And they always grow new leaves before shedding their old ones. Since they look green all the time, they're called evergreens.