Oak leaves are the foliage of the oak tree, a common type of tree found in many parts of the world. These leaves are typically lobed, with a distinctive shape that varies among different species of oak. They are usually dark green in color during the growing season and can turn vibrant shades of red, orange, or yellow in the fall. The leaves play a crucial role in the tree's life by photosynthesizing, which helps produce food for the tree. Additionally, oak leaves provide habitat and food for various wildlife, including insects and birds, contributing to the overall ecosystem.