A simulation tool to support the design of crop management strategies in fruit tree farms. Application to the reduction of pesticide use

Summary

Strategic decisions condition the orientation and associated agricultural practices of farms for many years, especially in fruit production where trees are planted for ten to fifteen years. However, this type of decision is rarely addressed in decision support approaches. An approach was developed to support strategic thinking in fruit tree farms through the use of a simulation tool called CoHort and built in Excel. CoHort evaluates the impacts of a given set of practices on the economic performances (gross and net margins), labour organization and phytosanitary performances (Treatment Frequency Index) of fruit tree farms. It has been built with cooperatives technicians and used with apple farmers in a partic-ipatory process to integrate the needs and objectives of the farmers and technicians. The approach alternates between simulations with the tool and discussions with the farmer. It is illustrated for two apple farmers in France aiming to reduce their pesticide use. The first farmer wanted to convert five hectares out of eight to organic production. Simulations showed that the raw margin was increased by 259%, the Treatment Frequency Index was reduced of 26%, but the labour demand was 9% higher. The second farmer wanted to replace 1.5 hectares out of 15 ha with a new scab-resistant cultivar. Results showed that the average TFI at the farm scale was decreased by 17%, the labour demand was similar, and the raw margin increased by 5%. Based on simulation outputs apple farmers could estimate the possible impacts of their projects to their farm. The tool flexibility allows using it with different farm structures and projects.