^"The area prior to the introduction of man 's activity is represented by one body of morphologic facts. The forms that man has introduced are another set. We may call the former, with reference to man, the original, natural landscape. In its entirety it no longer exists in many parts of the world, but its reconstruction and understanding are the first part of formal morphonology." 
^"The cultural landscape is fashioned from a natural landscape by a culture group. Culture is the agent, the natural area is the medium, the cultural landscape the result." 
^The European Environment Agency's planned forest naturalness index is an example of an attempt to define one type of natural landscape in Europe. The Agency lists forests in three categories: (1) Plantations; (2) Semi-natural; and (3) Naturally dynamic. The latter are "forests whose structure, composition and function have been shaped by natural dynamics without substantial anthropogenic influence over a long period of time".