1Working with Farmers: The Key to Adoption of Vetiver Grass Hedgerows to Control Erosion in

Cassava (Manihot esculenta Crantz) is the third most important food crop in southeast Asia and the most important upland crop in the northeast of Thailand. The crop is usually grown by small holders in marginal areas of sloping or undulating land. Most farmers realize, however, that cassava production on slopes can cause severe erosion, while production without fertilizers or manure inputs will lead to a gradual decline in soil productivity. Research has shown that cassava yields can be maintained for many years with adequate application of fertilizers or manures, and that there are various ways to reduce erosion. Adoption of recommended practices, however, has been minimal as farmers generally see little short-term benefits, while initial costs of establishing these practices may be substantial. In order to enhance the adoption of soil conserving practices and improve the sustainability of cassava production under a wide range of socio-economic and bio-physical conditions, a farmer participatory research (FPR) approach was used to develop not only the best soil conservation practices, but also to test new cassava varieties, fertilization practices and cropping systems that tend to produce greater short-term benefits. The FPR methodology was initially developed in 2-3 sites eac