Lovins, Amory B., L. Hunter Lovins, and Marty Bender. “Energy and Agriculture”
Pages 68, 69, 73 and 80

If we look at just the agricultural production consumed within the United States, slightly more than three calories of energy are invested per calorie of food obtained. When the energy costs for processing, distribution, and preparation are added onto the three calories, the total energy cost is about 9.89 calories of energy per calorie of food consumed in the United States ....

In contrast, the food systems of the rural populations of developing nations use an estimated 16.4 quads annually to feed about two billion people with a diet ranging from 1,800 to 2,400 calories per person daily (such diets contain much less meat than ours). This 16.4 quads is less than one-tenth of what the same number of people would consume were they utilizing the food system of the United States ....

About forty million tons of fertilizer are applied to America’s fields each year—approximately 330 pounds for each person in the country ....
At present, much of American farming and forestry is little more than a mining operation. A massive biomass fuels program that simply serves to put greater pressure on overstressed land would not only risk crushing a budding energy program but could also pull down much of American agriculture. Renewable must mean sustainable in the very long run. No biomass program can long endure unless it is based on the preservation and enhancement of soil fertility, water quality, and the biotic community on which agriculture depends.