Temperate deciduous forests are located in eastern North America, western Europe, parts of Asia, and southern South America. These forests experience seasonal changes with cold winters and warm summers. Common tree species include oaks, hickories, maples, and beeches which lose their leaves in autumn to conserve water. The forest has three layers - a top canopy layer, middle shrub layer, and bottom forest floor layer of grasses and ferns. These forests provide habitat but are threatened by human development and agriculture.