“Cleptoparasitic stored product pests are guilty of contaminating up to 10% of global grain supplies. Stored product pests can originate at the time of product production but drastically escalate during storage and transport.”
— Dr. Ted Granovsky
As Stored Product Pest Enemy No. 1, the Indianmeal moth (IMM), Plodia interpunctella, is an ongoing threat. IMM larval assaults do the most damage to infested materials because they anchor themselves to crevices with metabolic webbing. Larvae are mobile and can migrate into numerous adjacent areas. Observed larvae can resemble the color of food dyes within the products on which they’ve fed.
IMM All Points Bulletin
■ Life cycle is 25 to 135 days.
■ Female places 100 to 400 eggs (0.02 in. and non-sticky) on or in food materials.
■ The larvae — off-white, with brown heads — use webbing to anchor to crevices and cocoon.
■ Larvae are about 0.5 in. long at maturity.
■ Larval stage is about 14 days.
■ Pupal stage is about five days.
■ Adult stage is about seven to 10 days.
■ Adult length is 0.4 in.
■ Wingspan is about 0.6 in., and the outer third to half of the front wing is covered with reddish copper scales.
■ IMM are nocturnal, can fly and are attracted to lights.
■ These external feeders feast on grain and grain products, dried fruits, seeds, nuts, candy, dried red peppers and pet food (a particular favorite).
Because of product intimacy, an IMM infestation can remain incognito during early stages. All incoming raw materials should be sampled for insect presence. Correct species identification is essential to pinpoint the infestation.