EFFECTS OF ROTATION AND FERTILIZATION ON ECONOMICS OF CROP PRODUCTION IN THE BLACK SOIL ZONE OF NORTH-CENTRAL SASKATCHEWAN

Effects of changes in product prices and input costs on the economic performance of 10 spring wheat (Triticum aestivum L.) -based rotations grown on a highly fertile orthic Black Chernozemic silty clay loam soil at Melfort, Saskatchewan, were examined over the 27-yr period from 1960–1986. The rotations differed in frequency of summerfallow, N and P fertilization, and cropping sequence involving canola (Brassica napus L.), grass-legume hay [bromegrass (Bromus inermis Leyss.), alfalfa (Medicago sativa L.)], and legume green manure [sweetclover (Melilotus officinalis (L.) Lam)]. During 1960–1971 fertilized rotations received the generally recommended rates of N and P for the region, but during 1972–1986, fertilizer was applied based on soil tests. Net income, riskiness, and costs of production were calculated over a range of product prices and input costs. At wheat prices greater than $147 t−1, fertilized fallow-wheat-wheat (F-W-W), fertilized fallow-canola-wheat (F-C-W), and a 6-yr fertilized grass-legume h...