Interactive Physical Simulation Models for Sharing IPM Ideas with Farmers

Integrated pest management (IPM) practices which break pest lifecycles, reduce carry-over inoculum, or otherwise reduce the threat of or limit damage, may need to be applied at one point in the cropping cycle, whilst the effects of such action may only be apparent later in the season or even in the next season. Extension staffs attempting to introduce such pest management ideas piecemeal as Training and Visit impact points face a major challenge. Farmers may be highly reluctant to invest in actions whose beneficial effects, in relation to control of pests or pest stages which hitherto may have been unrecognized by them, appear to rest solely on the word of the extension agent. A method which I have experienced as extremely valuable for stimulating detailed debate between and among farmers and outside specialists on current pest management knowledge and possibilities for change is physical simulation modeling. The example described grew from efforts in the late 1990s in Southeast Tanzania to bring new pest control possibilities to the attention of cashew growers. The wider circumstances of the cashew case are reported elsewhere (Nathaniels, 1998). Such a modeling approach for communication may have wider relevance and applicability.