Comments on “Variability in Corn Response to Nitrogen Fertilizer in Eastern Canada” by L.A. Kablan, V. Chabot, A. Mailloux, M.E. Bouchard, D, Fontaine, and T. Bruulsema, Agron. J. 109:2231–2242 (2017)

Abstract

Core Ideas The experimental design was inappropriate in relation to the objectives. Eleven factors were confounded. Contrasting previous crops, methods of N application and N sources were assumed to be equivalent. Results of two‐way ANOVAs were not reported to support models and mean comparisons. Interpretation should consider non‐responsive trials and confounding factors. Incomplete statistical and economic analyses led to higher economic N rate.