Several people around the state use pheromone traps to monitor for different species of moths to detect the occurrence of early-season flights to aid in predicting their development. For years we had a network of pheromone traps to monitor the early-season flights of black cutworm adults, and several people still use pheromone traps to keep their eyes on this occasionally destructive pest. A lot of seed corn and sweet corn producers also use pheromone traps to monitor flights of corn earworms. Probably the most ambitious "trapper" in Illinois is Ron Hines, senior research specialist, Dixon Springs Agricultural Center, Pope County. Ron not only uses pheromone traps to capture black cutworms and corn earworms, he also sets traps to monitor the flights of European corn borer, southwestern corn borer, and fall armyworm. Every one of these pests can pose significant problems in southern Illinois, so Ron watches the moth flights carefully to keep tabs on their development.|
The sex pheromone lure for each species is supposed to be very specific, enticing the males of only one species. However, occasionally other species of moths are captured in traps that contain lures that are not supposed to attract them. Recently Ron captured some corn earworm moths in traps with pheromone lures intended to capture southwestern corn borer males. When he called the manufacturer of the lures, the representative of the company told him that the two lures (corn earworm and southwestern corn borer) are very closely related. They both have the same two major components. However, the lure for corn earworms has two additional minor components, whereas the lure for southwestern corn borers has one other minor component.
If you are using pheromone traps to capture a given species of moth and you begin finding more than an "accidental" number of another species, contact the manufacturer. Occasionally "bad batches" or "contaminated" pheromone is discovered, and occasionally the pheromone is old and not effective any more. However, as Ron learned, some pheromones are similar enough that occasional "mixups" occur. Overall, however, pheromone traps are extremely reliable pest management tools that will continue to provide valuable information.--Kevin Steffey