Full Text Article. Also available at: https://www.forskningsdatabasen.dk/en/catalog/2468256115This study was undertaken to compare alternative methods of pest control for insect pests in order to determine which methods has the highest efficacy against insect pests and the least detrimental side effects, while maintaining production and profits. The analysis was based on the experimental trials for three treatments: weaver ants, chemical insecticides and control. Data on yields, quantities and prices of inputs and output were collected and analyzed using inferential statistics (t-test), partial budgetary technique and marginal analysis involving dominance analysis. The results of partial budget analysis shows that a change from chemical insecticides treatment to weaver ants returned net benefits greater than zero by Tsh. 692 923 and Tsh.1019665 in cashew and mango plantations respectively. Similarly, positive net benefits was obtained when growers change from control to weaver ants treatment by Tsh. 504 989 and Tsh. 891 297 in cashew and mango plantations. The dominance and MRR analyses shows that if cashew and mango growers change from conventional agricultural practices to weaver ants, they would earn MRR of 1621% which is above minimum acceptable rate of return (MARR) of 100%. The t-test analyses show that weaver ant treatment is superior over conventional agricultural practices. The study concludes that weaver ant treatment was economically feasible and financially undertaking. Further field experimental trials will be repeated in the next two growing seasons to confirm results obtained in 2012.