Facts, Identification & Control
The Indianmeal moth life cycle is described as complete metamorphosis; egg, larval (caterpillar), pupal and adult stage. The adult is a small moth, about 3/8 inches long with a wingspan of about 5/8 inches. The wing color is generally gray but the rear half of the wing is rusty brown or nearly bronze. This wing pattern allows Indianmeal moths to be easily distinguished from other household moths. The larval stage is usually cream colored, sometimes with yellowish-green or pinkish shades, and has a dark brown head. Larvae may be seen as they wander in search of a place to pupate, or pass through the pupal stage. Often, the larval and pupal stages are seen on walls and where the wall and ceiling meet.
Behavior, Diet & Habits
The Indianmeal moth larvae can infest a wide range of dry foods such as dry pet food, birdseed, cereal, dried soup mixes, bread, pasta, rice, flour, spices, dried fruits and nuts. Lesser-infested foods include chocolate and dried flowers. When looking for Indianmeal moths, do not forget to look in dried plant and dried flower wreath arrangements. This wide range of suitable foods explains why this pest is considered by most experts to be the most common stored-food pest in homes and grocery stores.
Adults and larvae are common signs of an infestation. When flying, adults often appear to move in a zigzag motion instead of maintaining a direct flight line. Adults may fly to distant rooms in the house away from the infestation; therefore, they are commonly mistaken for clothing pests. Adults do not feed and normally rest during the day in dimly lit areas of the home. The larvae are surface feeders and cover their food source with silken webbing. Most of the damage to stored products occurs when the larvae spin massive amounts of silk that accumulate fecal pellets and cast skins in food products. The damage to stored products due to this contamination exceeds the amount of food eaten by the insects.
Controlling Indianmeal moths starts with a careful inspection to identify all the infestation’s food sources. Pay particular attention to items that have remained in the cupboard for long periods or foods that are loosely sealed or are in thin wrapping. Empty cabinets and pantries and check inside every food package. Get rid of any food that is infested. Use a vacuum to remove spilled food and insects from the empty shelves while paying close attention to the cracks and gaps between shelves and cabinet walls. Cleaning with soap and water is also needed. Any holes should be sealed. Remember that the larvae leave the food to change into adults. It is important to check the walls and ceiling in the pantry and the nearby area for crawling larvae. Larvae and pupae can be in cracks, behind appliances and even behind picture frames on the wall.
Store food products in sealed glass or plastic containers to prevent a re-infestation. If pet food or animal feed is stored in the garage or shed, check it too, since this often is a source of the infestation. Keep these products in tightly sealed containers. Also, food may be stored in the refrigerator.
Contact your pest professional for assistance and expertise to control Indianmeal moths.