Flour Moths

Indian meal moths (also called pantry moths or flour moths) larvae hatch in stored dry goods… flour, grains, seeds, cereal, chocolate, cake mixes, rice, nuts, dried fruit, dog food, birdseed, even tea, herbs and spices.

Adult flour moth & Pupa (left)-Alameda County Community Developement Agency, Adult Moth (right)-USDA Grain Marketing & Production Research Center

Description
Adult flour moths are approx. 2cm, brownish grey with a powdery substance on the wings. The larvae are very tiny and look like very small maggots. They are usually yellow or white with brown heads and measure around 1.5cm. Mediterranean flour moths resemble the indian flour moth and are very similar in appearance and their diet is basically the same. Indications you have them are finding the contents of cereal boxes clinging to the sides of the box in a mass of fine webs… or you find small, brownish moths flitting around inside your cupboard… or tiny cocoons and larvae in your dry goods like flour, pasta or beans.

Flour moth larvae (left)-USDA Grain Marketing & Production Research Center, Adult and larva (right)-Clemson University

Habitat and Lifecycle
Flour moths occur worldwide and are a particular pest in grain and flour mills. They can infest your pantry in no time if care is not taken. Control is extremely difficult. Female flour moths can lay 150-600 eggs at a time. They can hatch within 3 days at temperatures higher than 20 C (80 F) Eggs are laid in flour products and larvae feed and spin small loose webs. After feeding larvae pupate in the grains and emerge into adults. The lifecycle can be continuous year round.

Adults and larva-University of Missouri

Diet and Damage
Indian meal moths infest flour, bran, grains, all types of meal, cereals, pet food, livestock feed and other foodstuffs containing flour and grains. Adults do not feed and live only long enough to mate and reproduce. If you see any of them flying around a pet store, don’t even think of buying pet foods there and inform the owner. Once you have introduced them in your home, getting rid of them is extremely difficult.

Control Indian meal moths (a.k.a. “pantry moths” or “flour moths”)
1) Take all containers with the foodstuffs and place in the freezer for at least five days and then dispose of the foodstuff.
2) Clean out all your pantries and wipe very well with hot soapy water.
3) Line all the cracks and crevices inside the pantry with a sticky substance such as tanglefoot.
4) With a q-tip remove and destroy every larvae, egg and pupae that you find.
5) Use containers with tight fitting lids.
6) In summer months, store your cereals, grains and flour in the fridge to prevent an overpopulation.
7) I have successfully used Cupboard Moth Traps like the one pictured here (click the picture to order some). They work wherever food is stored. You put the cardboard traps in cabinets and pantries with food; they’re non-toxic and free of pesticides. The pheromone lure lasts for about 3 months. When the trap is covered with dead moths you just replace the trap with a new one. For light infestation you can also refresh the pheromone lure. They work great!