General Technical Documents Permaculture in Humid Landscapes
Pamphlet II in the Permaculture Design Course Series
Published: 1981-01-19
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The humid landscape is water controlled, and unless it is an extremely new landscape- volcanic or newly faulted--it has softly rounded outlines. When you are walking up the valley, or walking on the ridge, observe that there is a rounded 'S' shaped profile to the hills.
Where the landscape turns from convex to concave occurs a critical point that we call a keypoint.*