Pushing canola instead of windrowing can be a viable alternative

Compared with direct harvesting, windrowing canola (Brassica napus L.) crop reduces maturation time and seed losses caused by shattering; however, windrows are prone to wind damage. While direct harvesting canola may reduce costs and lower green seed content, new technologies are required to effectively reduce shattering losses. Pushing is a potential replacement for swathing where pod movement is restricted by mechanically lodging the crop and letting the crop mature while still attached to the root system. This system purports to limit shattering and improve seed quality. Trials were conducted over a 3-yr period in western Canada to determine the impact of pushing canola relative to windrowing. Field-scale trials showed that yield and oil content typically did not differ between canola pushed and windrowed on the same date. In plot trials conducted at Brandon and Indian Head, crop yields were not decreased nor were green seed numbers increased by early pushing. It was observed that pushing worked best when crop stand and growth were good as well as when canola was pushed at or before 30-40% of the seeds have changed color and therefore are physiologically mature. While further work is required to identify the earliest time at which a crop can be pushed without a negative impact on yield or quality, the current trials indicate that with canola, pushing could occur at the start of seed color change without any negative impacts on grain yield and oil quality. Key words: Canola, windrowing, pushing, harvest, yield, seed size, Brassica napus L.