Greater speed and depth increase the incorporation of surface residue. Heightened drought stress. Surface crusting indicates shallow compaction resulting from heavy rainfall. Seedling emergence is slowed by crust. This appearance in the top 13 to 18 inches indicates poor drainage critically-high in the root zone.
Poor drainage is a likely restriction on yield in that environment.
Zone tillage uses multiple coulters to prepare a seedbed as a band in the row area. The result of this additional tillage should be greater residue incorporation and faster soil warming than would otherwise occur if the row area surface were left under the nearly-complete cover of heavy corn residue on this poorly drained soils. This row tillage will also lessen the early - season bulk density and allow greater evaporative loss near the surface, also resulting in more rapid soil warming than would otherwise occur. Warmer early season soil temperature enhance early crop growth rate in this cool - Spring environment and may result in higher yield potential and faster dry down at maturity. Tillage lessens bulk density for the first few weeks of the season while undisturbed soil is initially more dense.