Three principal practices distinguish sustainable agriculture:
Sustainable agriculture protects soil in part through ridge tillage, which is a system of planting crops on ridge tops. Ridge tillage is attractive for two main reasons- lower production costs and greater soil conservation. Production costs are lower with ridge tillage in part because it requires less investments in tractors and other machinery than conventional planning. Ridge tillage features a minimum of soil disturbance from harvest to the next planting. A compaction-free zone is created under each ridge and in some row middles. Keeping the trafficked area separate from the crop-growing area improves soil properties. Over several years the soil will tend you have increased organic matter, greater water holding capacity and more earthworms. The channels left by the earthworms and decaying roots enhance drainage.
Sustainable agriculture involves the application of limited if any herbicides to kill weeds. In principle, farmers can control weeds without chemicals, although it requires additional time and expense that few farmers can afford. Researchers have found that combining mechanical weed control with some chemicals yields higher returns per acre than relying solely on one of the two methods. Conventional agriculture uses more chemical methods such as seeds that are genetically modified to survive when herbicides and insecticides. These are called "Roundup-Ready" seeds because of its creator Monsato Corp, sells it under the brand name "Roundup." Ridge tilling also promotes decreased use of chemicals which can be applied only to the ridges and not the entire field. Combining herbicide banding- which applies chemicals in narrow bands over crop rows- with cultivating may be the best option for many farmers.
Polyculture Sustainable agriculture attempts to integrate the growing of crops and the raising of livestock as much as possible at the level of the individual farm. In conventional agriculture, integration between crops and livestock generally takes place through intermediaries rather than inside an individual farm. Many farmers in the mixed crop and livestock region actually choice to grow only crops or only to rise animals. They sell their crops off to farms or purchase feed for their animals from outside suppliers. Sustainable agriculture's sensitive to the complexities of biological and economic interdependencies between crops and livestock.