Nitrate leaching from silage maize

Summary

During the last 20 years the area with maize in Denmark has increased dramatically and reached 163,000 ha in 2008. Silage maize is easy to grow, is a suitable fodder for cows and goes well with grass-clover in the diet. This means that silage maize is often found in crop rotations with grass-clover on sandy soils in western Denmark. The ploughing in of grass-clover fields poses a serious risk of increased nitrate leaching on a coarse sandy soil, even when carried out in spring. With increased maize cropping, there is therefore a need for strategies to reduce nitrate leaching after ploughing of grass-clover.In the ICROFS project, OrgGrass, we examined the effect of catch crop and slurry application on nitrate leaching from maize after a spring-ploughed grass-clover.