Soybeans
When and what tillage is required for soybeans?
Costs vary, depending on the type of implement used in field preparation and the type tillage system being considered. In general, only enough tillage is needed to control existing weeds. Tillage may be essential to prepare a seedbed, incorporate herbicides, and control existing weeds, but this depends entirely on your management decisions. Too much tillage can be costly, dry out the soil, damage the soil's physical condition, and delay planting, which could lead to lower yields. Burndown chemicals allow you the opportunity to substitute chemical weed control for tillage. Heavier soils are well suited for this practice, and by minimizing tillage, you can better manage these soils.
Recently, some positive benefits have been observed where deep tillage has been performed. This option should be performed in the fall while fields are dry. Fields should be smoothed and then planted minimum till in the spring.
Yield responses have varied, but the greatest yield increases have been observed on the mixed soils with the clay soil being less. Conventional wisdom has been that clay soils crack so they subsoil themselves. Research at Stoneville shows that while they do crack, deep subsoiling broke the profile up further, thus allowing roots to explore more of the profile.
Subsoiling is an expensive operation and one that will not be able to be conducted every year. If the subsoiling operation does not occur in the fall before the onset of fall rains, the benefits will be minimal if any.
In addition, if it were not for practicing rotation with some early maturing crops, or using early plant of early maturing soybeans, growers would not be able to conduct deep tillage in the fall most years. Approach deep tillage with an open mind; it is not for all fields and will not be accomplished every year. Research is showing that every other year to every third year may be sufficient. If this holds true, growers need to practice tillage rotation. Till portions of your acreage each year, but not so much as to cause major planting delays.
For additional information, see Mississippi State University Extension Service Publication 1289.
