Fig. 5. Phosphorus shoot concentration as a function of N concentration of corn at St-Louis in 2004 and Ste-Catherine in 2005 under limiting (20 kg N ha^–1) and nonlimiting N conditions (100 kg N ha^–1). Solid line, linear regression (P = 1.00 + 0.094N) for nonlimiting N conditions as presented in Fig. 3; dashed line, linear regression (P = 1.25 + 0.104N) for limiting N conditions as presented in Fig. 4; dotted lines, data from one sampling date.