Comparison of sensors and techniques for crop yield mapping

The implementation of site-specific crop management is dependent on the variations in yield and yield potential within a field. Crop yield maps are important for both the implementation and evaluation of site-specific crop management strategies. Management decisions and evaluations based on yield maps must take into consideration the accuracy and resolution of the maps. An impact-based yield monitor and a volumetric yield monitor were compared. The effect of different dynamic models of combine grain flow on the calculated instantaneous yields were investigated. Both simple time delay models and first order models could be used to model the grain flow. In general, a simple time delay model with minimal smoothing provided the best yield maps. Yield maps developed using different methods of Kriging and other mapping techniques were compared. The maps showed the same general trends. However, localized yield features were represented differently due to the methods used for developing the maps and the degree of smoothing.