Carbon Cashflow

Cycling more carbon through the soil should be your top priority

Carbon is a hot topic in agriculture these days. You’ve likely heard about carbon sequestration programs. But let’s set that aside. Getting more carbon to cycle through the soil should be your top priority. Carbon is the currency of life. The cyclic flow of carbon through plants, animals and soil provides the energy source (food) for soil microbes. This carbon-powered microbial activity drives everything from nutrient cycling to decomposition to water purification. It also creates the glues that build soil aggregates, which are the building blocks for healthy, well-functioning soil. 

Soil organic matter is about 50 percent carbon. It serves as a critical buffer for physical, chemical and biological stability in the soil. Generally, the more organic matter a soil has, the greater its capacity to store and supply nutrients and water. Low-organic-matter soils are less productive and usually less profitable to farm. 

Carbon is the unit of exchange that enables the biological community in the soil to function. Root exudates are liquid carbon that plants pump into the soil to feed microbes in exchange for nutrients. Think of organic matter as a savings account, whereas root exudates are like the cashflow to fund a checking account. If there is extra cashflow, some of it can be moved to savings for a rainy day. If the checking account runs dry, microbes will tap into the savings account to get their food, and organic matter levels will decline as they eat through their cash reserves. The biological community in the soil starves without a continual influx of carbon, just like your community would go hungry if the grocery store shelves were running empty. 

When the flow of carbon through the soil is interrupted, farmers and ranchers eat through their own cash reserves by buying expensive inputs to replace the lost soil function and productivity. Carbon as the cash cow that drives farm and ranch profit. If you invest in cycling more carbon through your soil, you will be paid many dividends in the long run.