CONSERVATION TILLAGE AND INPUT USE

There continues to be a question as to the overall effectiveness of co nservation tillage practices in reducing the impact of agricultural pr oduction on the environment. While it is generally recognized that wat er runoff and soil erosion will decline further, as tillage and mulch tillage systems are not used more extensively on cropland, what will h appen to pesticide and fertilizer use remains uncertain. To gain some insight into this, the conservation tillage adoption decision is model led. On the assumption that the decision to adopt conservation tillage is a two-step procedure, the first decision is whether or not to adop t a conservation tillage production system and the second concerns the extent to which conservation tillage should be used-appropriate model s of the Cragg and Heckman (dominance) type are estimated. Based on fa rm-level data on corn production in the United States for 1987, the pr ofile of a farm on which conservation tillage was adopted is that the cropland had above-average slope and experienced above-average rainfal l, the farm was a cash grain enterprise, and it had an above-average e xpenditure on pesticides and a below-average expenditure on fuel and c ustom pesticide applications. Additionally, for a farm adopting a no-t illage production practice, an above-average expenditure was made on f ertilizer.