Economics of rotation and tillage systems for the Dark Brown soil zone of the Canadian Prairies

Abstract

The influence of tillage on the economic performance of two rotation systems, fallow-oilseed-wheat ( Triticum aestivum L.) (F-O-W) and oilseed-wheat-wheat (O-W-W), was assessed in a 12 year study carried out on a medium textured, Orthic Dark Brown soil at Scott, Saskatchewan. Oilseeds were flax ( Linum usitatissimum L.) and canola ( Brassica campestris L.), alternated in the oilseed year to minimize potential problems with disease and weeds. Economic calculations (expressed in Canadian dollars) were based on 1990–1991 input costs and product prices. Gross returns averaged 46% higher for O-W-W than for F-O-W systems (average $310 ha −1 versus $213 ha −1), and were significantly higher for O-W-W in 8 out of 12 years. Tillage management did not influence gross returns from F-O-W; for O-W-W, zero tillage resulted in higher gross returns than conventional tillage in 3 out 12 years. Nonetheless, in both rotations gross returns tended to be higher with zero tillage, reflecting higher grain yields owing to improved soil moisture conditions. Annual production costs were higher for O-W-W than for F-O-W rotations (average $217 ha −1 versus $166 ha −1) because of greater requirements for machine operations and other purchased inputs. Production costs were also higher for zero- compared with conventional-tillage management (average $183 ha −1 versus $149 ha −1 in F-O-W, and $225 ha −1 versus $209 ha −1 in O-W-W, respectively). Compared with conventional tillage, zero tillage provided savings in labor, machine operation, and machine overheads (average $7–$10 ha −1) but these were more than offset by higher herbicide costs. Net returns were generally highest for O-W-W systems. In the O-W-W rotation, zero tillage was more profitable than conventional tillage if herbicide costs were reduced by 15% or more from their 1990–1991 cost levels; at higher herbicide costs, conventional tillage was superior. The results also showed that producers who are risk averse are not likely to use zero-tillage management with a F-O-W rotation owing to the high costs for weed control on summer fallow. Such producers would more likely choose a F-O-W rotation with conventional-tillage management if expected product prices were low: as prices increase, they would probably consider using the O-W-W rotation with either type of tillage management. We concluded that, in contrast to the past, there is some economic incentive for producers in this region to adopt cropping systems with improved soil conserving features.