Rotational Benefits of Forage Crops in Canadian Prairie Cropping Systems

Abstract

Including perennial forages in cropping systems is recognized as one of the best ways to enhance agricultural sustainability. While rotational benefits of forages have been established in small plot research trials, there is no documentation of whether these benefits are being observed on commercial farms, or whether producers manage forage stands to maximize rotational benefits. A survey of 253 Manitoba and Saskatchewan producers known to include forages in their crop rotations was conducted in 1992. The survey area was divided into six agroclimatic zones and correspondence analysis was used to test whether responses differed across the survey area. Sixty-seven percent of respondents indicated a yield benefit from including forages in the crop rotation, with the greatest yield benefit observed in welter zones of the survey area. Eighty-three percent of the respondents observe weed control benefits for one (11% of respondents), two (50% of respondents), or more (33% of respondents) years after forages. The majority of respondents indicated that their forage acreage would not increase in the future. Average forage stand duration varied significantly (P < 0.10) with agroclimatic zone, ranging from 3 to 5 yr in welter areas (south-central Manitoba) to 6 to 9 yr in the driest areas (south Saskatchewan). The two most common reasons cited for forage stand termination were reduced forage yield and damage by pocket gophers (presumably Thomomys talpoides and Geomys bursarius). Less than 12% of respondents cited rotational considerations as their primary reason for terminating forage stands, indicating that producers are not managing their forage crops to maximize rotational benefits. Producers relied heavily on tillage in both forage crop establishment and forage stand termination phases of the production system. It was suggested that decreasing the amount of tillage and fallow associated with forage-based cropping systems would not only facilitate increased cycling of forages in rotations, but also increase agricultural sustainability.