Weed Management Strategies and Their Economic Implications in Cassava Production in South East Nigeria

This study examines weed management strategies and their economic implications for cassava production in South East Nigeria, assessing the cost-effectiveness and agronomic performance of alternative weed control approaches in Anambra, Enugu, and Imo States. Weed management accounts for 30 to 40 percent of total cassava production costs in South East Nigeria, making it a critical economic determinant of profitability for smallholder farmers. Identifying cost-effective weed management options is essential for improving cassava farm economics. This study uses a combination of controlled field experiments and farmer on-farm trials across six sites in the three states, testing conventional hand weeding, pre-emergence herbicide, post-emergence herbicide, integrated hand weeding plus herbicide, and mulching approaches. Total weed management cost per hectare, cassava root yield, partial budget analysis, and economic threshold analysis are computed. Farmer experience and satisfaction surveys supplement the agronomic data. Findings reveal that integrated hand weeding plus early pre-emergence herbicide achieves the highest root yield of 28.6 tonnes per hectare at a total weed management cost 38 percent lower than conventional twice-hand weeding. Pre-emergence herbicide alone is the most cost-effective single strategy when labour costs are high. Mulching produces strong results in farms near organic material sources. The study concludes that the optimal weed management strategy is context-dependent based on farm labour availability and herbicide access. It recommends decision-tree-based extension guidance that matches farmer context to the most economic strategy.

Keywords: weed management, cassava production, South East Nigeria, economic analysis, herbicide.