Preventing stable fly in Costa Rica

Pineapple in Costa RicaPineapple is a profitable growth crop for many large farming enterprises in Costa Rica. New sweet varieties are expanding the market for the fruit in Europe and Asia. Paraquat has become essential for post-harvest land preparation. It helps desiccate the tough pineapple crop residues. The stable fly (Stomoxys calcitrans) provides an additional challenge. It is the most common biting fly pest of confined livestock. Its irritating bites can cause considerable distress to animals and result in reduced production. Heavy infestations of more than 50 flies per animal can reduce weight gain by 25 percent and milk production by 40 to 60 percent. The stable fly thrives in the decaying pineapple crop trash as it ferments in the hot sun. When pineapples became popular, stable fly infestations were so bad that cattlemen wanted the fruit farms shut down. The Ministry of Agriculture wants pineapple growers to control the stable fly with a range of measures. Growers use paraquat followed by shedding and disking to deal with the trash. Fly traps are also mandatory for monitoring potential outbreaks. Any build-up is treated with insecticides. Using paraquat as part of post-harvest crop residue management brings double benefits. It allows Costa Rican farmers to control the stable fly successfully, thus protecting livestock, while also continuing to produce world-class pineapples. Local growers confirm that no other herbicide has the power required to stop the stable fly from breeding in the crop trash.