Injecting liquid manure into the soil instead of spreading it on the surface can help crops grow better and outcompete weeds. A study compared injecting manure with surface application over three seasons in barley and oats. When combined with weed harrowing or herbicide spraying, injecting manure led to better weed control and higher crop yields. Barley responded faster to the injection method than oats, becoming a more competitive crop. Overall, injecting manure closer to the crop helped reduce weed biomass and improve crop yield.