We have now felled forest enough everywhere, in many districts far too much. Let us restore this one element of material life to its normal proportions, and devise means for maintaining the permanence of its relations to the fields, the meadows and the pastures, to the rain and the dews of heaven, to the springs and rivulets with which it waters down the earth.
George Perkins MarshApart from the hostile influence of man, the organic and the inorganic world are ... bound together by such mutual relations and adaptations s secure, if not the absolute permanence and equilibrium of both ... at least a very slow and gradual succession of changes in those conditions. But man is everywhere a disturbing agent. Wherever he plants his foot, the harmonies of nature are turned to discords.
George Perkins MarshThe equation of animal and vegetable life is too complicated a problem for human intelligence to solve, and we can never know how wide a circle of disturbance we produce in the harmonies of nature when we throw the smallest pebble into the ocean of organic life.
George Perkins MarshThe improvement of forest trees is the work of centuries. So much more the reason for beginning now.
George Perkins Marsh