THE ECONOMICS OF WHEAT ROTATIONS ON A HEAVY CLAY CHERNOZEMIC SOIL IN THE BLACK SOIL ZONE OF EAST-CENTRAL SASKATCHEWAN

The effects of changes in product prices and input costs on the economic performance of 14 spring wheat (Triticum aestivum L.) rotations on a calcareous Black chernozemic heavy clay soil at Indian Head, Saskatchewan were examined over 25 yr. The rotations comprised fertilized and unfertilized treatments and several mixed cereal-oilseed and cereal-legume systems. In 1960–1977 the fertilized rotations received N and P according to the generally recommended rates for the region, but during 1978–1984 fertilizer was applied based on soil tests which resulted in substantially higher rates of N for stubble crops. Four of the rotations showed good economic performance under most reasonable economic situations. These included fertilized fallow-wheat-wheat (F-W-W), fertilized continuous wheat, unfertilized sweet clover [Melilotus officinalis (L.) Lam.] green manure-wheat-wheat (Gm-W-W), and unfertilized fallow-wheat-wheat- legume hay-hay-hay (F-W-W-H-H-H). During the first 18 yr, Gm-W-W provided the highest net inc...