Indian Meal Moths
- Scientific name: Plodia interpunctella
- Size: 1/4th to ½ an inch long
- Color: Bronze, copper or dark gray with a light tan or cream band
- Shape: Long and trigangular
- Found in: The entire United States
The Indian meal moth gets it’s name not from the actual country of India, but from it’s first description, from when cornmeal was known as “Indian meal.” It is the most common pest moth in the United States. They are an irritating and potentially financially troublesome pest inside the home. The Indian meal moth is not a significant economic pest outside the home, but on farms and in households, they can cause considerable bother. The adult moth is not actually the part of the life-cycle that causes the damage, that part being the larval stage.
Signs of Infestation
The common homeowner can tell that they have Indian meal moth one of two ways: if the moth has a significant population inside the home, the adult moths can be seen flying around the inside of the home, most evidently around bright household lights, to which they are attracted. The adult females commonly lay their eggs near sources of food. When the larvae hatch, they can penetrate even unopened packages to get at the foodstuffs within. The larvae leave a distinctive silk webbing behind as they eat, which is an easily seen sign that you may have and infestation of Indian meal moths. You can also sometimes see the matured larvae crawling the walls near food sources as they search out a place to spin their cocoons in preparation of pupating into adult moths.
The Indian meal moth likes dark, warm spaces with easy access to food for their larvae. Most, if not all, of the stages of the Indian meal moth are very sensitive to temperature, freezing temperatures proving fatal. They tend to congregate in the pantry area of the home, however, in the wild, they can populate bird and squirrel nests, feeding on the food stores and leftovers there. In the farm setting, the Indian meal moth is most common wherever grain is stored silos and feeding areas for livestock.
Outside of the home, the Indian meal moth is most dangerous to grain stores and can reproduce in alarming numbers if allowed unchecked access to large amounts. If the grain is being sold for consumption, moth infestation can drop the net weight of the stores and render them useless for the commercial market. Inside the home, the larvae of the Indian meal moth can sometimes eat it’s way through the packaging around grains such as oatmeal, cornmeal and flour. If the packing material is thick enough, the larvae will need a crack, hole or weak seam to gain access, which is why it is important to keep your dried foodstuffs inside of air-tight containers. Once inside the larvae will decimate the supply and then retreat elsewhere to pupate. Since a single female moth can lay upwards of 100-300 eggs in a single breeding, this can mean a serious waste of dried goods.
Treatment and Prevention
The best prevention for the Indian meal moth is keeping the areas most at risk in proper condition. This includes keeping your pantry areas clean, dry and your dried goods in air-tight containers, which will minimize the need for pesticides should and infestation occur. After the moth is established in the home the only sure way to get rid of an infestation is to completely get rid of the infested food and then clean the pantry and surrounding areas to make sure that all stages of the moth life-cycle are eradicated.