Trees,grasses, and weeds: species choices in farmed-developed contour hedgerows

Innovations intended to conserve soils and improve soil nutrient cycling have not been widely adopted because of technical problems and lack of fit with farmers' cricumstances. Research in Claveria, the Philippines, facilitated and monitored farmers' adaptation of contour hedgerows to fit their particular needs. Farmers tested different establishment methods and many hedgerow species. They initially planted a combination ofGliricidia sepium (a legume tree) andPennisetum purpureum. (grass). Later adoptors chose fodder grasses (especiallySetaria spp.) or naturally occuring vegetation in their hedgerows-either solely or in combination with other species, including weeds such asRottboellia cochinchinensis identified as crop problems. Upland rice and maize farmers who adopted contour hedgerows from 1987 through 1991 were interviewed in 1992. Although hedgerow-crop competition, grazing by neighbors' cattle, and added labor were problems, farmers viewed hedgerows as a way to reduce soil erosion and provide fodder. Farmers planting mulberry were disappointed after a silkworm project folded. Farmers now face the problem of soil nutrient depletion, leading to fallowing of fields with hedgerows and shifting to other parcels. A farmer decision tree model of the minimum necessary criteria for sustainable adoption of contour hedgerows is hypothesized.