Enhancing pea productivity through winter intercropping with canola (Winter Peaola)

Ontario farmers are looking to diversify current corn-soybean-winter wheat rotations with high value alternative crops. The recent expansion of winter canola acres is an example of the successful adoption of an alternative crop that brings value and adds diversity to the typical crop rotation. Where permissible, the production of winter crops allows for the escape from many of the pests and disease that can hinder spring crops and promotes the temporal diversification of crop management tools and inputs. While the practice of intercropping peas and canola is not new, the shift from spring peaola to winter may help dry pea production escape pest and disease life cycles while providing the well established benefits of reduced pea lodging and enhanced productivity relative to the monocultures of either crop. Field trials were established at the Harrow Research and Development Center in autumn 2020 and 2021 to evaluate the impact of winter canola plant populations density on the yield and land equivalency ratio (LER) of winter peaola. Results indicated that yield and LER of winter peaola were directly correlated to overwinter survival. Winterkill in canola was less than 10% in both years but ranged from 5% in 2021 to 70% in 2022 for peas. When pea survival was low, LER of winter peaola ranged from 0.96 to 1.17; when peas survival was high, LER ranged from 2.5 to 3.2. These results suggest that, with breeding efforts aimed at improving overwinter survival, winter peaola could be a viable and productive option for farmers in southern Ontario.