Influence of Tillage and Fertilizer Placement Methods On Corn Yield.

Tillage and fertilizer application methods could alter plant yield and quality of corn production.  Thus, a field experiment was conducted at the Sand Mountain Research Station located in the Appalachian Plateau region of Northeast Alabama on a Hartsells fine sandy loam to evaluate tillage (conventional vs. no-tillage) and fertilizer application practices in a corn production system. The fertilization treatments consisted of broadcast applied and subsurface banded (B) poultry litter (PL), broadcast applied and subsurface banded (B) urea ammonium sulfate blend (UAS), broadcast applied ammonium sulfate (AS), and a control (non-fertilized check) (C).  The PL and inorganic fertilizers were applied at a rate 170 kg N ha^-1 approximately two weeks following emergence. Differences in yield, averaged across tillage, between fertilizers were observed for fertilizer sources and placement.  The impact of fertilizer on yield was in the order of AS > PLB > UASB > UAS > PL > C. A comparison of fertilizer treatments in the no-tillage (NT) only showed that subsurface banding fertilizer provided the greatest yield compared to broadcast application. This was attributed to greater N retention in soil. Addition of cover crops in the NT resulted in greater corn yield compare to without a cover crop. The addition of cover crops most likely restricted nutrient loss from surface water runoff during intense rainfall events. An interaction was observed between fertilizer application methods and cover crop, suggesting that the greatest yield increase is observed when PLB and UASB are used in a cropping system with cover crops.