But sustaining good yields in dryland requires that you plant adequate populations. Unlike sorghum or wheat, which can compensate by tillering, corn needs to have plants to make yield if conditions are good. One should always plant for a good year, and hope that it will be. Effect of plant populations on dryland corn yield in a no-till environment, Norcatur, KS, 1999. CV 4.1 0.56 0.7 Table 2.
Rotations are important.
If you are in a conventional tillage system, you can stay in continuous wheat for several years without too much problem. But continuous wheat in a no-till system will lead to poorer and poorer yields. Looking at it from the soybean side, an additional 9.3 bushels of beans were realized over continuous soybeans when rotated with either wheat or sorghum. Some of the problems that develop when staying in a continuous monocrop such as continuous wheat or sorghum include increased disease pressure, insect infestations, and a natural selection for weed species that are similar to the crop. For continuous wheat, the weed that becomes the dominant problem is cheat.