Intensive Crop Rotations Research Articles

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 income for wheat prices ranging from 73 to 221 $ t−1; F-W-W-H-H-H generally ranked second highest. During the last 7 yr, fertilized continuous wheat was most profitable for wheat prices greater than 180 $ t−1. Continuous wheat, F-W-W, and F-W-W-H-H-H were about equal and provided the highest net income for wheat prices between 145 and 180 $ t−1, while at wheat prices below 145 $ t−1 net income was highest for the legume-containing rotations. Except for the fallow-wheat rotation, higher economic benefits were obtained when fertilizer was applied based on soil tests than when based on the general recommendations for the region. Further, the application of fertilizer reduced the cash cost per unit of wheat produced for the more intensive crop rotations. Rotations containing high proportions of fallow or legume crops generally had the lowest frequency and risk of financial loss.Key words: Crop rotations, net income, input costs, income variability, riskiness