<p><strong>A couple of red ants crawling up one's body is sure to cause jitters, but a colony of them on a cashew tree can actually help reduce damage to the invaluable crop. Findings indicate that red ants or weaver ants (Oecophylla smaragdina)— known for their painful bites and formic acid sprays—are a potential biological control agent against a wide range of pests found in several fruit and cash crops. The cashew crop, in particular, is susceptible to quite a few pests such as the stem and root borer, tea mosquito bug, apple and nut borer, thrips, leaf miner, and the leaf and mealy bug. Of these, the tea mosquito causes the most damage.</strong></p> <p><strong>Recent experiments conducted by scientists of the Indian council of agricultural research (ICAR) at Old Goa have shown that red ants colonized on cashew trees can actually help control the tea mosquito bug. "This is a harmless way of treating the pest. It is also easy for farmers to manage," N P Singh, director of the ICAR research complex, Old Goa, said. Singh and another scientist, R Maruthadurai, reported their findings at a national conference on innovation in traditional practices for cultivation of fruit, vegetable and plantation crops that was held in Old Goa recently.</strong></p> <p><strong>The scientists used 75 predatory ant colonies from other trees for their experiment. Initially, the ant nests were not directly put up on the control trees. "Food material such as dried fish and sugary water were provided to help the colonies establish themselves. Tree branches were connected by fine nylon thread for easy movement of ants," the report stated.</strong></p> <p><strong>After about 30% of the foliage had been colonized by red ants, five trees were selected at random for observations. Five other trees that bore no red ants were also monitored during the flushing, flowering and fruiting phases of the crop from November to February. "The results revealed that the damage score of 1 (on a 0-4 scale) was recorded in trees colonized by red ants, whereas a maximum damage score of four was recorded in trees without red ants. The tea mosquito bug adult and the nymph population were significantly lower in plants colonized by red ants. A larger number of productive shoots was also observed in trees that housed the predatory ants than those that had none," the study stated.</strong></p>