By DR. Robert L. Ellsworth, Ph.D.
Agriculture is increasingly being held accountable for the environmental interaction of pesticide and fertilizer over-usage. It is of paramount importance that farmers understand the implications of managing the relationship between fertilizer, soil, crop and water usage. In order for them to appreciate what is happening in the area of ecology, it is important that we prepare a definition of the impact of pesticides and fertilizers on crop yield, current and future.
The soil has tremendous power to digest and use components designed to improved yield. Modern Agriculturalists, both scientists and farmers, have utilized these to the ultimate and in many cases created environmental problems. The most important of these components is the one most neglected, ORGANIC MATTER. Organic matter takes many forms as it is digested in the soil by the soil microbial community.
Organic matter is applied primarily as the residue of the preceding crop, and is turned under by various tillage methods chosen by the farmer. Organic matter is made up of three major components; Carbon (C), Hydrogen (H), and Oxygen (O). Since up to 55% of the crop body dry weight is comprised of Carbon, we need to pay more attention to how it can best be reutilized by the following crops.
When properly digested by Aerobic micro-organisms, much of the carbon is released into the soil and atmosphere surrounding the crop, as carbon dioxide. It is then available for absorption by roots and foliage to form new sugars, starches, and proteins. As we limit the amount of of carbon dioxide available to the growing plant, so are the growth and reproduction capabilities also limited. It therefore behooves the farmer to pay more attention to the fate of the organic matter (crop residue).
Other factors that are beneficial to the following crop might include the formation of polysaccharides that aid in the formation of soil tilth. Soil tilth is the factor in soil that forms very small clumps of soil particles and flocules. These flocules are particles of sand, silt and clay glued together by the polysaccharides from the proper digestion of organic matter, which is primarily done by the action of aerobic micro-organisms. The tilth thus formed allow water to penetrate more readily into the soil, and also provides greater absorption of water as well as air. These actions aid in the reduction or complete elimination of soil compaction. The greater absorption capacity is provided by the presence of small air pockets that are formed within the flocules, as well as the silt and clay particles involved. This water is more readily available to the plant root as it is not held tightly to the flocule.
The formation of Humates in the soil by the completed breakdown of organic matter allows for greater retention of fertilizer material, such as Nitrogen, and greater ability of the plant to utilize the fertilizer when it is contacted by the plant root. On the other hand, it has been demonstrated that Phosphorous and Sulfur will pass through an organic contact process before becoming available for root absorption.
The more complete digestion of crop residue by soil micro-organisms produced by the use of ViTech’s ViBasic and/or ViClout are thus important not only to improve water penetration and soil aeration, but also to help provide more efficient usage of fertilizer already in the soil, or that to be applied to the soil.