The greenwood is a legal category

Matter of the Greenwood Topic

Summary: Forest in this period does not mean woodland; it means land under forest law, where the king's venison and vert are protected by a separate and notoriously resented jurisdiction with its own courts and officers. Poaching is not theft but an offence against the crown's private pleasure. The outlaw in the greenwood is standing in the one place where royal law is at its most arbitrary, which is exactly why the setting carries the politics it does.