A CASE-STUDY APPROACH TO COMPARING WEED MANAGEMENT STRATEGIES UNDER ALTERNATIVE FARMING SYSTEMS IN ONTARIO

When research was initiated into comparing alternative methods of mana ging weeds in Ontario's major field cash crops, no field trial data ex isted. Twenty-five farmers were therefore surveyed for their productio n data on corn, beans and fall-seeded cereal grains, including weed ma nagement practices. input costs and wage rates, yields and product pri ces. Nine farmers were classified ''conventional'' because of their he avy dependence on synthetic herbicides, which were routinely broadcast on the three focus crops. Nine farmers were classified as ''reduced i nput'' if they placed reduce dependence on herbicides for at least one of the focus crops. Seven organic farmers placed zero reliance on her bicides, using instead substitutes such as crop rotations, smother cro ps, soil tillage and timeliness of field operations. Although organic farmers spent the most time and money on weed control, their overall d irect costs of production were lowest for all three focus crops. Crop gross margins were highest on organic farms, partly because of lower p roduction costs, but also because of higher product prices along with comparable crop yields. Linear programming model results for whole-far m analyses revealed highest net farm incomes on organic farms and lowe st on conventional farms, in part due to lower overhead costs on organ ic 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 or reduced-i nput methods of weed management offer viable alternatives to conventio nal approaches.