Fig. 5. The soil NO₃–N concentrations in the 0- to 20-cm depth compared with the number of croppings after termination of five excessive biosolids applications at West Bennett, 1990–1998. Where significant treatments x cropping interactions were found, averages labeled with the same lower case letter are not significantly different according to Least Significant Difference comparisons across all croppings at P 0.10.