Understories are the layers of vegetation that grow beneath the canopy of large trees in a forest or woodland. Other terms for understories include underbrush, undergrowth, shrub layer, or subcanopy layer. These layers are important as they provide habitat for a variety of insects, birds, and small mammals. They also play a significant role in regulating the moisture and temperature of the forest floor and in nutrient cycling. Maintaining a healthy understory layer is essential for the overall health and biodiversity of forest ecosystems. Synonyms for understories are often used interchangeably, depending on the context and the type of vegetation present in the forest.