phosphorus and potassium require mining, using the brute
force of oil-powered machinery to dig deep into the earth.
Pesticides require fossil fuels, so do irrigation equipment,
milking machines, and so on. Even if organic farmers use
manure as fertilizer, they still rely upon fossil fuels, and not
just to power machinery. Often they acquire this manure from
livestock on nonorganic farms, and that livestock was fed for-
age and grain fertilized by chemicals that were created using
I refer to the great Two Hundred Years' War, the war
between the city and the land. Probably on account of
religious prejudices, the primitive peasants stubbornly
held onto their “bread.” In the thirty-fifth year before
the foundation of the One State our contemporary petro-
leum food was invented.
—Yevgeny Zamyatin, We (New York: Dutton, 1924).
Since most of the new carbon ejected into the atmosphere
comes from fossil fuels, the carbon footprint of food can be
reduced by using less oil, coal, and natural gas. Because these
fuels are expensive, farmers and food manufacturers have
always been in the game of conserving energy, and have done
so mostly by increasing their productivity. As technology has
evolved over time to reduce energy costs, the carbon footprint
of food has likewise fallen.
There is more to a carbon footprint than energy use. One
reason beef has a larger footprint than pork or chicken is
because cattle are ruminants, and ruminants expel carbon
as they burp—and they burp about once a minute. A wheat
farmer who plows his soil might emit more carbon than a
wheat farmer using no-till methods, as breaking and turning
the soil releases carbon into the atmosphere.
The carbon footprint of food even depends on consumer
behavior. It takes more gasoline to drive to the grocery store