In a Northern Italian context, a field pea cover crop was tested as mulch for the maize crop. The roller crimper effectively terminated the cover crop (15 t per ha of wet biomass). However, the mulch did not last long enough, probably due to a narrow C/N-ratio and biologically active soil. The maize plants did not have enough time to develop and shade the entire soil surface. Weeds started to sprout through the decomposing mulch. For the test conditions, this cover crop has proven unsuitable as a long-lasting mulch to control weeds. No fertilization and no irrigation were applied. The maize yields amounted to about 5 t per ha.
Practical recommendations
• The cover crop needs to be sown as accurately as the main crop. Poor cover crop stands do not result in good mulches.
• The effectiveness of the mulch depends on the amount of mulch biomass. However, more biomass also means more difficulty for the planter.
• On soils with low organic matter content, additional nitrogen fertilisation should be considered