An
old-growth forest — also termed
primary forest,
virgin forest,
primeval forest,
late seral forest, or (in
Britain)
ancient woodland — is a
forest that has attained great age without significant disturbance and thereby exhibits unique
ecological features and might be classified as a
climax community. Old-growth features include diverse tree-related structures that provide diverse wildlife
habitat that increases the
bio-diversity of the forested ecosystem. The concept of diverse tree structure includes multi-layered canopies and canopy gaps, greatly varying
tree heights and diameters, and diverse tree species and classes and sizes of woody debris.