The adults also damage grain by boring into the kernels and leaving them covered with powder from the chewed material. The rice weevil is similar to the granary weevil in both appearance and habits. The name is misleading, however, since it infests other grains besides rice. Adults can fly and, in warm climates, can cause widespread damage to corn, wheat and other grains before harvest. Common to both stored grain and cereal products, Indian-meal moth larvae cause damage in corn meal, packaged foods, bagged grain and grain in storage.
Attack is confined to surface layers of stored shelled corn and small grains.
In the case of stored ear corn, however, feeding occurs anywhere, since the moths crawl among the ears to lay their eggs. Larval feeding is characterized by a webbing of the material infested. The mature larvae then often leave the material and crawl about in homes or buildings in search of a place to pupate. Both the adult and larva are large and easy to see. Both stages feed mainly on the germ of stored grains, but may also attack milled cereal products.