Fig. 5. Effect of spring-seeded (1992) ryegrass cover crop (incorporated in May 1993) on soil NO3–N concentrations at various depths in May 1993 and 1994, including standard error bars.
Fig. 5. Effect of spring-seeded (1992) ryegrass cover crop (incorporated in May 1993) on soil NO3–N concentrations at various depths in May 1993 and 1994, including standard error bars.