A needle of a tree is a type of leaf that is adapted to cold and dry climates. Unlike broad leaves, needles have a small surface area and a thick cuticle that reduce water loss. Needles also contain antifreeze chemicals that prevent them from freezing in low temperatures. Some trees, such as pines, spruces and firs, have needles all year round and are called evergreens. Other trees, such as larches, have needles that change color and fall off in autumn and are called deciduous.