A Case Study Approach to Comparing Weed Management Strategies under Alternative Farming Systems in Ontario

When research was initiated into comparing alternative method's of managing weeds in Ontario's major field cash crops, no field trial data existed. Twenty‐five farmers were therefore surveyed for their production data on corn, beans and fall‐seeded cereal grains, including weed management practices, input costs and wage rates, yields and product prices. Nine farmers were classified “conventional” because of their heavy dependence on synthetic herbicides, which were routinely broadcast on the three focus crops. Nine farmers were classified as “reduced input” if they placed reduce dependence on herbicides for at least one of the focus crops. Seven organic farmers placed zero reliance on herbicides, using instead substitutes such as crop rotations, smother crops, soil tillage and timeliness of field operations. Although organic farmers spent the most time and money on weed control, their overall direct costs of production were lowest for all three focus crops. Crop gross margins were highest on organic farms, partly because of lower production costs, but also because of higher product prices along with comparable crop yields. Linear programming model results for whole‐farm analyses revealed highest net farm incomes on organic farms and lowest on conventional farms, in part due to lower overhead costs on organic farms, and in part due to greater enterprise diversification and to greater self‐sufficiency in material inputs. These case study results need broader‐scale testing to verify the conclusion that organic or reduced‐input methods of weed management offer viable alternatives to conventional approaches.