ABSTRACT
This chapter examines energy inputs in the food system and assess food vulnerability due to the heavy dependence of agriculture on fossil fuels--a fast disappearing resource. Before the development of agriculture and the manipulation of the natural ecosystems to produce certain food plants and animals, wild plants and animals were the only source of food for humans. Gradually, more intense alteration of the ecosystem, employing "slash and burn" agricultural technology, developed and increased food yields. The inputs in crop production can be assessed by examining the inputs in an important crop, corn. In this analysis, three corn production systems will be compared: hand-powered, tractor-powered, and horse-powered. The energy flow in tractor-powered agriculture is distinctly different from that of man-powered agriculture. Corn production in the United States typically relies on heavy machinery for power. The energy flow in corn production can be examined another way by substituting horse power for fossil fuel and the tractor.
