A hollow tree is a tree that has a cavity or space inside its trunk or branches. This can occur due to natural processes like decay, disease, or damage from storms. Hollow trees can provide habitats for various wildlife, including birds, insects, and small mammals, making them important for biodiversity. In some cases, hollow trees can also be used by humans for various purposes. For example, they can serve as natural shelters or be used in art and crafts. Additionally, foresters often study hollow trees to understand their health and role in the ecosystem.