Site-Specific Manure Application Effects on Corn Yield and Nitrogen Status

Manure, a renewable resource, is an excellent source of nutrients that can be substituted for synthetic fertilizers. The organic matter in manure can enhance the physical and chemical properties of soils, especially infertile soils, as these soils typically contain low levels of organic matter and nutrients, and have low water holding capabilities. The application of manure to these relatively infertile and unproductive sites within a field, can restore the productivity of problem areas back to acceptable levels. The objective of this study was to evaluate manure application for improving crop yield and nitrogen (N) status in less productive areas within a field. The treatments included applications of site-specific manure (SSM), uniform manure (UM), uniform commercial fertilizer, and a no treatment check. Field strips 12.2 m wide (16 corn rows) and 680 m long were used in two years (1997 and 1998). Geographic information systems (GIS) and remote sensing techniques were also used in this study to geo-reference the field and to compare aerial photography reflectance bands to corn grain yield and chlorophyll meter readings. For the SSM treatment, manure was applied to areas within the field where organic C was