Organic matter is the key to soil quality, but building soil organic matter levels can be slow and expensive. There is an alternative. Research shows (Franzluebbers, 2002) many soil functions improve when organic matter is concentrated in the top 2-3″ of the soil, and that, for many soils and environments, this may be the most effective way to improve soil quality. Soil organic matter (SOM) is crucial for many soil functions, and so has been a primary indicator of soil quality. The % organic matter of the top 6, 8, or 12″ of soil is often used to evaluate whether a soil is improving or degrading. In gardens and small fields, it is relatively easy to increase the quantity of SOM. Not so in large fields where crop residues are often the only source of organic matter, and where increasing SOM by even 0.5% may require a decade of costly
This is a part of the series The Promise of GMOs. Do GMOs live up to the promises of the biotech industry? In the case of increasing conservation tillage, there is data to back up industry claims.