Pine trees are called evergreens because their leaves (called needles) don’t turn colors in the fall, and they keep them all winter. This is good because pines offer small birds, such as chickadees, sparrows and finches shelter during the winter from wind and predators. They do lose their needles over time, but not all at once. The fallen needles don’t decay as rapidly as leaves allowing for burrowing and nesting materials for birds and small animals.