Stored Food Pests

There are many insect pests that infest food and although control can be difficult, prevention is relatively simple.

Stored food pests can be organized into groupings: beetles, weevils and moths. One of the most common is the saw-toothed grain beetle–a brown beetle about 3 mm (1/8 inch) long. Other problem food pests include: drug-store beetles, granary weevils and several types of small moths, including the world’s most common stored food pest: the Indian meal moth.

Eggs are laid by food pests on or near a food source. The eggs hatch into worm-like larvae. The larvae can chew through plastic and paper packaging to get to food. When they are full grown the larvae “pupate” (form cocoons) in cracks or crevices in the cupboards or in the food itself. The pupae gradually become adults and the adults re-infest the food or travel to new, food to lay eggs.

People usually discover they have an infestation when beetles or moths are found in cereal, spices or other food. Sometimes the beetles may be seen crawling on the kitchen counter, or moths are noticed fluttering in the kitchen.

A wide variety of food can be attacked by stored food pests. This food includes: cereal, crackers, dried fruit, nuts, flour, cake mixes, dry pet food and spices.

Prevention

• Keep food in tightly sealed containers
• Clean up spilled food promptly
• Buy only small quantities if food is not used often
• Check food packages carefully to be sure you do not bring insects home from stores

Control

• Infested food must be discarded (or treated by heat or cold) to kill the adults, larvae and eggs
• Thoroughly clean all infested areas with soap and water
• Use sticky traps (http://www.contech-inc.com/products/pantrymothtrap/) to capture beetles or moths. Some traps use a lure to attract the insect
• For persistent problems, contact a pest control specialist

– Alan Vaudry, B.Sc., M.P.M.