Crop rotation for successful winter wheat production

Non-Peer ReviewedSuccessful production of winter wheat on most of the Canadian prairies requires direct seeding into standing stubble of the previous crop. Crop rotation is often seen as a limiting factor to the expansion of winter wheat acres in this system as the previous crop needs to be harvested early enough to allow winter wheat to be seeded by late August or early September, depending on location. This project was initiated with the objective of developing a practical tool to assist farmers in selecting seeding dates for several spring crop species so that winter wheat can be planted during the optimum period for fall establishment. Degree-days, or heat unit requirements, to produce a physiologically mature crop were determined for Polish canola, barley, oat, mustard, Argentine canola, hard red spring wheat, and flax. Daily climate data was then used to determine the probability of the crops reaching physiological maturity by specific dates in the fall when they were sown between May 1 and June 9 at selected locations in western Canada. Future plans are to expand the number of sites to include over 9,000 station years of weather data so that risk maps and fact sheets with tables can be produced to assist farmers in planning rotations for winter wheat. While the initial objective of this project has focused on winter wheat production, there are a large number of additional uses for this type of management tool