ABSTRACT
Cultivated soils of the Canadian prairies are young and occupy an area of about 30 million hectares. The soil at Swift Current is a Swinton loam to silt loam, an Orthic Brown Chernozem developed from aeolian deposits that overlie glacial till. The soil at the experimental site is situated on gently sloping land. The various plant and soil characteristics were analyzed as a split-plot with the year as main plot and rotation phase as subplot. To assess the influence of rotation phase on soil organic matter carbon and nitrogen, samples taken in the five 3-year rotations in 1990 were analyzed as a split-plot with rotation as main plots and rotation phase as subplots. The advantage of the system containing the winter cereals was its ability to produce adequate amounts of crop residues in drought years, to protect the soil from erosion because of its much shorter fallow period compared to the spring-seeded crops.
