Indian Meal Moth
March 2023 Issue
Indian meal moth is found worldwide and is associated with over 200 stored commodities. This pest can be found in bakeries, grain processing facilities, breweries, warehouses, retail stores, homes, and outdoors in urban and grain processing environments. It is by far one of the most widespread and well-known pests of stored grains, seeds, beans, spices, nuts, pet food, dried fruit, candy, and any finished packaged product made from any of these items.
It is the larval stage of the moth that does all of the damage to products and they are adept at penetrating packaging. The larvae go through five to six instars before pupation. Often, the larvae will wander some distance away from the infested food source shortly before pupating. This can be confusing in that where you see these large larvae may not be where the actual infestation is located. One of the keys to controlling this moth is to locate the source of the infestation and treat or eliminate it. This is why a properly executed pheromone monitoring program is essential to control this pest.
After emergence, the female releases a sex pheromone which is very attractive to male moths. This pheromone has been synthesized and is used as a lure in sticky traps for monitoring this species. It is important to note here that these monitoring traps are precisely that; for monitoring the presence or absence of Indian Meal Moth. They are not and were never meant to be control devices.
The purpose of a pheromone monitoring program is to provide you with data so that you can make better decisions on corrective actions. The first data point a pheromone monitoring program should provide is insight into when you have received an inbound product that is infested. This can be very simple. If you go from zero moths to 200 in a single day in the monitor by your receiving area, you can make some assumptions that you were just sent some infested product. Find it, isolate it, and dispose of it. The second data point your program should provide is the potential location and product that may be infested. If a pheromone monitoring program is properly set up in your facility, you can use the data from multiple monitors to help you identify and locate the infested product that is causing you the problem. Find it, isolate it, and dispose of it.
Controlling the Indian Meal Moth can be very challenging. Trying to do without a properly executed pheromone monitoring program is nearly impossible as these insects are highly mobile. Under the right conditions of temperature and humidity, their numbers can grow to astonishing levels within a couple of months, and the source of much product damage, load rejections, and customer complaints, all of which can be damaging to your brand. If you handle or process high-risk ( for stored product pests) products or ingredients, make sure you have a robust pheromone monitoring program. It can help save you from costly corrective actions.