The question is not what kind of yield increase can you expect; rather, what yield variations are there from dry to wet years. Good growing seasons in the mid-South produce close to maximum yields without supplemental irrigation. If the drier seasons do not decrease yield significantly, then irrigation may not be a good investment. Because of the variation in soil types and soil depths in the Delta, some farms do not have large yield swings from wet to dry years, while others have dramatic swings. Irrigation development on the weaker soils in our region is a much better investment than on the better deeper soils. We do not typically increase the maximum yield potential much above the better yields that are produced on a farm with good rainfall. The biggest advantage of irrigation in this region is the leveling of yields to a more predictable level and taking out big yield swings from wet to dry seasons. Irrigation should generally be developed on the drier shallow soils first.