Agronomy Library > Annual Weeds

Managing Carbon - Do You C what I C?
Author: Dr. Dwayne Beck, Dakota Lakes Research Farm
Date Created: November 21, 2007
Last Reviewed: November 21, 2007
Modern agriculture has become extremely dependent on the use of energy from outside sources. This outside energy is used for manufacturing the tools and inputs used in agricultural production, for most production operations, and to process and transport the agricultural products after they are harvested. In fact, much of the “productivity and efficiency” credited to modern agricultural production is probably related to use of outside energy inputs most of it in the form of what we will call geologic carbon. In addition, what brought most of our European ancestors to the prairies originally was the store of vast store of geologic carbon contained in the prairie sod. Mining the nutrients and biological energy from this source was made easier and faster through use of geologic carbon in the form of coal, natural gas, and oil. This dependence on geologic energy links farm profitability closely to the ratio between the price of energy and crop prices. One only has to examine historic price ratios to gain insight. Wheat had an average price of $1.37 per bushel in 1970. Oil was $3.39 per barrel that same year. There is no need to comment on the present ratio. As this ratio has changed, farmers have become more efficient in their farming practices. No-till is part of that change. The savings associated with eliminating tillage are substantial but they are not sufficiently large to offset the ever widening ratio between the price of wheat and oil. For instance, it takes energy equivalent to one gallon of diesel fuel to produce, transport, and apply 5 lbs of nitrogen fertilizer. Obviously something needs to be done to modify the way we do things. Understanding carbon cycling better is a way to begin this change.  open the attached PDF for the complete paper