Maize in permanent grassland: effects of strip tillage and mechanical weeding on soil properties and yields

Silage maize is a valued crop in grassland-based dairy farming due to its high yield and feeding value. However, the delivery of ecosystem services (biodiversity, soil quality, carbon sequestration etc.) is greatly reduced in maize, compared to permanent grassland. To combine the ecosystem services of maize and grassland, a cropping system was developed for silage maize sown in living permanent grassland. In a field experiment, grass was superficially mulched, either full-field or in strips, maize was sown and weed control was carried out mechanically, both full-field and in strips. The control included chemical full-field grass killing and chemical weed control, without soil tillage. Measurements at the end of the growing season show no significant treatment effects in maize yield and soil quality, but clear negative effects of superficial tillage on earthworm biomass. We conclude that in a fertile soil, silage maize can be grown without use of herbicides and that a strip of permanent grassland reduces the negative impact of superficial tillage for the earthworm population.