Indian Meal Moth

The Indian meal moth is a very common insect pest found in stored food products within the home. Indian meal moth larvae feed on any grain or grain product (flour, cornmeal, oatmeal, grits, etc.), seeds (including bird seed and dried beans), nuts, chocolate, dried fruit (such as raisins), and so forth.

The female moth lays between 60 and 300 eggs, singly or in clusters, on or near the foodstuffs. Be careful to thoroughly check all dried food before purchasing at the store, as Indian meal moth may be present. Eggs hatch in 2 to 14 days with larvae or “tiny whitish caterpillars” dispersing within a few hours. Larvae move to foodstuffs, and feed on stored grains, flours and spices.  Some food becomes matted with silken webbing which can be seen if food boxes are inspected carefully. The larval stage is the feeding or “pest stage” and may range from 2 to 41 weeks, depending on the temperature. In stored grains, feeding is done at the surface.

When ready to pupate, mature larvae leave their tubes and spin a silken cocoon. They often migrate or “wander” a considerable distance from their food source before finding the pupation site, often in cracks and crevices. Some crawl up walls to where the wall and ceiling meet or crawl to the top of the cupboard to spin the cocoon in which they pupate and from which new adult moths emerge. Mating occurs and the life cycle is repeated. The life cycle may range from the shortest period of four weeks to the longest of 300 days. Under good conditions, the entire life cycle requires six to eight weeks. However, in cold climates, larvae pupate in March. Moths emerge in April.

Generations overlap as the season progresses. There may be five generations per year in some locations. The life cycle depends on temperature, taking two to six months in temperate zones and three to four weeks in warm climates. Narragansett Pest Control sells a pheromone trap designed to attract the IMM. Come visit our showroom today!