Cost-benefit analysis of wood and food components of agri-silviculture in Nigerian forest zone

Costs and revenue of agri-silviculture in Nigerian forest zone were estimated. Two crop combinations were considered: Gmelina arborea Roxb., a hardwood species was interplanted with (a) yam (Dioscorea rotundata) and maize (Zea mais) and (b) cassava (Manihot utilissima) and maize. Agri-silviculture increases the farmer's income in this zone. The ratios of total cost to revenue are 1:2.3 for yam and maize and 1:2.4 for cassava and maize. The farmer's net income is U.S. $4065.86 from yam and maize and U.S. $2790.24 from cassava and maize. When the trees are clear-cut after five years, the ratio of cost to revenue is 1:2.4. The farmer's net income from wood is U.S. $2872.95. If 5 per cent of the farm families in the area practices agri-silviculture, each family cultivating one hectare, there will be enough fuelwood after five years' growth.