TECHNOLOGY
The Heavy Plow
The wheeled, coulter-equipped plow with moldboard that broke the heavy clay soils of northern Europe — requiring eight oxen, cooperative agriculture, and ultimately the reorganization of village life.
The light scratch-plow (ard) of the Mediterranean world was adequate for thin dry soils but defeated by the deep wet clay of northern European river plains — precisely the richest agricultural land on the continent. The heavy plow, emerging between the sixth and ninth centuries, combined a vertical coulter that cut the sod, a horizontal plowshare that undercut it, and a curved moldboard that turned the cut sod over. It could break the clay the ard could not touch. But it required enormous draft power — typically eight oxen — which no single peasant family owned. The plow therefore required cooperative agriculture, producing the open-field system in which families held strips of land within larger communal fields, plowed cooperatively and farmed individually.
In The You On AI Field Guide
The heavy plow is White's second major agricultural case study in Medieval Technology and Social Change, and its analytical structure mirrors his treatment of the stirrup and the collar. A mechanical change produces a capability