Why do evergreen plants have needles rather than leaves?

The evergreens, pines, spruces, and hemlocks are able to survive winter because they have developed a way to protect their foliage. Instead of flat leaves, pine trees have needles. These needles are the key to the Winter survival of the pine tree.Needles cut evaporation so trees can save water to survive in the winter.

Additionally, the needles will help to store the water that the tree does collect.