Soil Organic Matter

When we talk about soil health, we look at things like tilth, compaction, erosion, microbes, and etc.  One easy indicator of soil health is organic matter levels.  Check your soil test reports and see if organic matter levels are going up or down.  Declining organic matter levels could indicate that you are doing too much tillage or removing too much residue.  High yielding crops will help maintain organic matter and tilth.

For additional information check out this Crops and Soils magazine article.  It covers many aspects of soil organic matter.  One of the concerns in the magazine and one I have seen in other venues as well is the concern that removing crop residues for biofuels will lower soil organic matter.  Some long term research is needed on the subject.  It is possible that removing residue, but continuing to use no-till could maintain or reduce the amount of soil organic matter lost.  Why?  A good bit of the organic matter produced by the crop is in the roots.  Not tilling the soil would reduce exposure to oxygen and slow down oxidation of organic matter.  I am speculating here.  That is why I am suggesting research.