A forest is more than just a bunch of trees growing next to each other. A forest is a very complex system of animals and plants, living in and on fertile and suitable soil. Forests are divided up into five different levels or layers. These levels are the canopy, herb, shrub, understory, and the forest floor. The canopy layer is the top layer. This is where photosynthesis takes place and it's also where the leafy tops of the trees are. This layer is home to a variety of insects and squirrels. The next layer is the understory. This is made up of smaller trees and is home to birds and climbing animals. The third layer is known as the shrub layer. It is made up of shrubs and vines. It also provides nuts and berries. The next layer is the herb layer. This layer is made up of soft green plants and wildflowers. Birds, insects, snakes, and toads also nest there. The last and final layer is the forest floor. This is the thick fertile soil covered by twigs, branches, insects and detritus.