Soil moisture plays a big role in the decision of whether or not to till in the fall. When considering tilling, there are a few factors to keep in mind. First, is tillage necessary to help with heavy residue? And second, is tillage necessary to help relieve soil compaction?
If heavy residue could be a potential issue for planting in the spring, and soils are wet in the fall, then the use of light tillage should be considered. Light tillage will mix the residue into the soil and start the decomposition process. The disk or vertical tillage tools will be best for this task. Also, consider chopping stalks after harvest, which can assist in residue decomposition and result in less soil structural damage than tillage under wet conditions.
When it comes to soil compaction, moisture is an important factor. Wet conditions can cause compaction, especially in heavy clay content soils. Pay attention to soil density in fields, as this also influences compaction. Soil density is determined by soil organic matter, soil texture, the density of soil minerals (sand, silt, clay) and their packing arrangement. A good rule of thumb for soil texture is the coarser it is, the higher its density.
When soil moisture levels are high, it is best to not do anything that will further increase the compaction situation. It is better to wait for better soil moisture levels rather than compacting soils further by running heavy equipment.