Are your crop rotations costing you money?

Abstract

Crop rotations under irrigation have focused on limiting the impact of weeds and disease on canola. With the development of canola cultivars with a wide range of herbicide tolerances weed control is no longer a major reasonable rotation. Likewise there is chemical control and genetic resistance to blackleg. This trial was established to determine the degree of yield loss which might be expected in a “high risk” crop rotation vs a “low risk” rotation. The “high risk” (canola-pea) rotation has 7-17% lower yields than the “low risk” (wheat-flax-wheat-canola). At current prices, rotations involving wheat have higher returns. However, at higher canola prices or lower wheat prices the high risk rotation could be more profitable. Cropping decisions need to consider all aspects of risk management and the risk to canola yields from “high risk” crop rotations has not been excessive.