Indian meal moths usually get into a house by way of some dry goods like cereal, pasta, or flour. The eggs and larvae are small enough to pass through the fine mesh screens used by manufacturers for filtering purposes, so they may be present even in new, unopened food packages. Indian meal moth larvae feed on the outer germ of grains. As they eat, the larvae spin a silken thread and leave behind a telltale trail of webbing.
Full-grown larvae abandon the grain source to find a place to spin their cocoons. Homeowners may find crawling larvae or cocoons on the walls and ceilings of their kitchens, or even hidden behind appliances.