http://www.fromthewilderness.com/fre...ating_oil.html

Extract

In the United States, 400 gallons of oil equivalents are expended
annually to feed each American (as of data provided in 1994).7
Agricultural energy consumption is broken down as follows:

· 31% for the manufacture of inorganic fertilizer

· 19% for the operation of field machinery

· 16% for transportation

· 13% for irrigation

· 08% for raising livestock (not including livestock feed)

· 05% for crop drying

· 05% for pesticide production

· 08% miscellaneous

Energy costs for packaging, refrigeration, transportation to retail
outlets, and household cooking are not considered in these figures.