About Indian Meal Moth

Indian meal moth is a common pest found in homes. It belongs to Pyralidae family and Plodia genus. It is also referred to as pantry moths or flour moths. It is about 3/8 inch long and the length of wings is about 5/8 inch. The body color of Indian meal moth is generally dirty gray. It has unique bi-colored wings. The part of wing near to the head is light gray in color and the remaining section is dark brown or copper in color.  

The female Indian meal moth lays 60 to 400 eggs on her food source. The eggs are non sticky in nature and they are smaller than 0.5mm. The eggs are hatched in 2 to 14 days. The larvae of Indian meal moth is normally termed as wax worms. The larvae are off-white in color and have brown heads. The larvae stage lasts from 2 to 41 weeks. The time required for larva to become an adult varies, depending upon the temperature conditions. The larva is about 12mm long. They feed on nuts, coarsely ground grains and other food products.

The newly hatched Indian meal moth larvae are too small to see and are usually yellowish, pinkish or greenish in color. They have three sets of legs near the head and five sets of prolegs on the abdomen.

The mature larva of the Indian meal moth spins silk thread on their food source. They can cause tremendous problems in commercial flour operations by clogging machinery with their webbing.

The adult Indian meal moth does not cause any harm to the food products, but its larva is the main culprit that contaminates the stored food products. When the larvae emerge into pupa stage, they wander away from food products so that they can spin a loose cocoon in some corner. They spend some weeks in the pupa stage and become adult moths. If the weather is warm, Indian meal moth requires six to eight weeks to become an adult, whereas it takes six months in winter.

The caterpillars of Indian meal moth infest on foods, including dried fruits, nuts, powdered milk, cereals, flour, spices, dry pet food and birdseed. They are phototrophic and fly toward light.

The Indian meal moth can reproduce, when the weather conditions are favorable. The life cycle of this moth requires four to forty five days (from egg to adult). In a year, seven to nine generations can exist.

A female Indian meal moth lays 100 to 300 eggs on food products either in single or in groups of twelve to thirty. The larvae feed on fine materials found inside the grains. As they are too small in size, it is difficult to exclude them from grains and packaged foods. However, they cannot chew through packages. If there is any hole in the package, they can then enter through that hole. They become responsible for grain losses.

Indian meal moth feed on grains intended for both humans and animals. They contaminate the grains, as they leave droppings and silken webs in the grain. If the grain is stored for a longer period, then the grain loss may be more due to the infestation of Indian meal moth. The grains infested with moths can reduce its value and can make it unfit for consumption.

Indian Meal Moth Removal Tips

It is important to maintain quality of grains especially in storage units by adopting effective Indian meal moth control measures. Measures such as residual sprays and sanitation must be followed strictly especially if the grains are stored for a long period of time. Grain weight is significantly reduced by the Indian meal moth. These moths also lead to dockage of the grain due to webbing and contamination.

It is vital therefore to take efforts to prevent the grains from being infested by these moths. Sanitation is absolutely essential to reduce the usage of pesticides. Sanitation process involves removing the older grain and cleaning the container well before storing new grain. You will have to ensure grain is removed from walls, floors and corners in a thorough manner.

An excellent method of preventing Indian meal moth infestation in grains is to use the grain dryer fan on a regular basis. Moisture build up is brought under control and the grain temperature is reduced by the increased air flow in the grains. This creates a condition where insects cannot thrive.

If grains are expected to be stored for more than six months, then sanitation only  is not enough. It is necessary to spray the grain surface with a residual spray after storing in the bins.

In case of extreme Indian meal moth infestation, fumigation can be considered. However this should be the last resort because if not handled with caution, fumigants can be hazardous.

Indian meal moths found in kitchens and pantries can be removed in a similar manner. In homes, we can find them laying eggs in dried food, grain products, grains, pet foods, chocolates, candy, seeds and powdered milk.

Indian meal moth traps are available in the market which can be used effectively to capture them. These traps use the moth pheromones which excites the male moths. As more and more male moths are captured, mating activity comes to a standstill thereby reducing and eventually eradicating the population. It is essential to use the traps on a continued basis to ensure the adults emerging from existing eggs are captured immediately.

The most common traps found are the triangular traps which are pre baited. All you need to do is to remove the release paper from the trap. Doing this exposes the glue. You now have to fold it into the triangular shape and the trap is ready. These traps are baited with pheromones. This trap can be secured to a surface or can be hung from the ceiling. Use a double stick tape measuring ¾ inches on the back of the trap.

Pantry pest traps are excellent options and are very effective and powerful. These traps have a major effect on pantry pests, especially the Indian meal moths. Whether it is the safe pantry pest traps, the propest pheronet or the revenge moth trap, you must keep in mind a few vital points as you place them.

Traps have to be placed close to the area where a lot of pest problems occur. This includes areas where dried food is stored such as kitchen, pantry, basement or even garage.

The next important step is to ensure there is a lot of air circulation in the area where you place the traps. Care must be taken to ensure the trap will not be damaged by traffic or swinging doors. Traps must also be placed within ten feet of the infested food stuff for best results.

It is advisable to prevent Indian meal moths to avoid contaminated grain problems. Sanitation can help to reduce the usage of pesticides. It is important to store new grain only after removing the old grain and the dust in the grain bin. This can reduce the possibility of moth infestation.

Damage Caused Due to Indian Meal Moths

Many species of this insect category infest milled cereal products like flour and breakfast food and are found in Utah. They attack on foods stored in damp conditions like basements and root cellars. Their presence makes the materials out of condition and to a stage of molding.

Larvae of both Indian meal moths chew paper, cardboard, cloth and burlap containers. The infested materials shed larval skins, cocoons, dead adults and fecal material. The color and odor of the infested foods show marked changes. They are surface feeders. Damage caused due to Indian meal moths are by spinning excessive amounts of silk that mix up fecal pellets, egg shells and cast skins in the food products.  This damage is more than the food consumed by the insects.

Indian meal moths can be prevented from entering food areas by storing the materials at lesser moisture levels in air-tightly sealed glass or plastic containers. Temperatures of 130 to 140 deg F for duration of 60 minutes kill all the developmental stages of the insects.  If the infested material is treated in freezing atmosphere of less than 0 deg F for 7 days, the insects can be eradicated thereby damages can be averted.  Both heating and cooling do not remove cocoons, insect bodies or fecal material. Adult Indian meal moth appears to be fluttering than maintaining a direct line of flight. They are attracted by light and fly to those bright rooms from the infested areas away from them. They relish fruit juice or sugar baits.