An agronomic evaluation of conservation-tillage systems and continuous cropping in East Central Saskatchewan

Soil degradation in east central Saskatchewan is due primarily to frequent summerfallowing, and the excessive use of tillage for weed control and seedbed preparation. A five year study was conducted at four locations to determine the agronomic viability of a crop-fallow and a continuous-cropping sequence under conventional (CT), zero (ZT), and minimum (MT) tillage systems using cereal and oilseed crops. Similar yields were obtained with all tillage systems. Plant densities were not affected by tillage or cropping system. Differences in crop water use, and consequently, yield were generally associated with differences in spring soil moisture (SpSM) between crop-fallow and continuous-crop treatment. Overall, continuous-crop yields were 88% of yelds for crops grown on fallow when averaged over all crops and sites. The effects of tillage and cropping systems on SpSM were dependent on soil type. When differences in SpSM were observed, the increase was associated with ZT, MT, and fallow cropping. The study concluded that conservation tillage and continuous cropping are viable alternatives to traditional summerfallow cropping practises, and refinements in crop and water management could further improve productivity.