Influence of changing tillage practices on crop production

The most efficient and practical way of protecting the soil against wind and water erosion is with surface and anchored crop residues. The rate and extent of crop establishment is not adversely affected by conservation tillage provided shallow seeding is used and adequate seed-to-soil contact is achieved. Soil water conservation can be enhanced with conservation tillage systems and the amount conserved is directly influenced by the type and amount of crop residues present and the agro-ecological zone. Crop residue decomposition is 1.5x slower on the surface than when buried and the rate of decomposition can be explained almost entirely by the location and nitrogen content of the residues and growing degree days. Grain yield can be improved with conservation tillage and is directly related to the amount of extra water conserved, regardless of the crop. Crop establishment, which is critical in forage production, can be improved with conservation tillage. Removing forage stands with herbicides as opposed to tillage favoured subsequent crops. Further research is required on the manipulation of stubble height and row spacing to enhance water conservation and to determine the impact of such changes on crop growth and development, weeds and plant diseases. There is need to develop crop-specific conservation production practices for each agroecological zone.