Released March 4, 2011
LITTLE ROCK, Ark. - Finding unwanted visitors skittering or flying about in the kitchen or pantry often indicates an infestation of pantry pests, said John Hopkins, extension entomologist-urban with the University of Arkansas Division of Agriculture.
"To most people, the identity of these pests is uncertain, and frequently their origin is mysterious," he said. "If not detected early, the resulting infestations can spread from package to package in the pantry."
Any food item that remains unused and exposed in some dark cabinet or drawer for long enough is subject to infestation. Most stored food pests reproduce quickly, and have several to many generations in a single year. Many are active year-round.
Moths and beetles, the adult forms of most common pantry pests, are often attracted to lights or window and their presence may indicate an infestation.
Pests may invade under their own power or be brought into the house in already-infested packages. "The presence of stored-food pests is not an indication of uncleanliness since they may be unknowingly brought home," said Hopkins.
Where infestation begins
Common materials subject to infestation include dried foods and grain products such as flour, cake mixes, cornmeal, cereal, dry pasta, grits, powdered milk, graham crackers, spices, chocolate, nuts, dried fruit, birdseed, dog and cat food, and fish food. Infestations may also be found in decorations using maize, whole seeds, dried flowers or potpourri.
"Even seed- or bean-stuffed toys are susceptible," he said.
The most common pantry pests include beetles, ants, weevils and Indian meal moths. These can be present in both adult and immature forms, said Hopkins.
Indian meal moths are considered the most troublesome of the grain-infesting moths. They cause damage via the larvae spinning silken threads as they feed and crawl, thus webbing food particles together.
Other common pests include the confused and red flour beetles. These beetles and their larvae generally infest milled grain products such as flour and cereals. They often hitchhike into homes through infested flour, and some can survive on food accumulations in the cracks and crevices of cabinets and furniture.
There are several storage and preventative measures that can be taken:
- Store food in glass or plastic insect-proof containers with tight-fitting lids.
- Susceptible items that must be stored for long periods should be placed in a refrigerator or freezer.
- Purchase seldom-used foods in small quantities to avoid long-term storage.
- Use older packages before new ones.
- Do not mix old and new food items, as this can spread an infestation.
- Never purchase food if its packaging is broken.
- Keep cabinets, pantries and counter tops clean and free of crumbs and spillage.
- Dispose of any food that is expired or shows signs of infestation.
How can infestations be dealt with?
Sometimes it's too late for prevention.
"The simplest and most effective non-chemical control measure is to locate the source of the infestation, place it in a sealed container and discard for removal by your garbage service," said Hopkins. "Following removal of the infested material, remove all food, food packages, utensils and dishes from the cabinets, shelves and storage areas.
"Then, use a strong-suction vacuum cleaner with proper attachments to clean all spilled food from cracks and crevices in food storage areas and from behind, under and in appliances and furniture." This helps prevent against future infestations.
"Scrub food storage areas with hot, soapy water and let it dry," he added. "Then cover surfaces with clean, fresh paper or foil before replacing food or cooking utensils."
Say it was some food or a decorative item worth keeping. What then?
Intense heat or cold is the answer in this case, said Hopkins. "All life stages of pantry pests may be killed by placing infested material to extreme heat or cold," he said. Methods include heating infested food in a shallow pan in the oven at 120 degrees Fahrenheit for one hour or at 130 degrees for 30 minutes; heating in a microwave for five minutes; heat-treating dried fruits or vegetables by placing in a cheesecloth bag and dipping in boiling water for six to 10 seconds; or freezing infested material in a deep freeze set at zero degrees Fahrenheit for four days.
Sifting the following these treatments will remove any insect fragments. Seeds saved for planting may have reduced germination as a result of these treatments.
"After the insects are killed, contaminated food might be used outdoors during the winter months for birdfeed," said Hopkins.
Although many people reach for insecticides first, these should only be used as a last resort. "The use of insecticides labeled for pantry pests is supplementary to sanitation and proper storage," he said. "They may be used if removal of infested material, thorough cleaning and proper storage fail to eliminate the problem."
Remember to read and carefully follow the directions on the container label before using any pesticide. Contact your local county extension agent for assistance in identifying pests and for control recommendations.
- 30 -
University of Arkansas, http://www.uaex.edu/news/march2011/0304Pantry_Insects.htm
Contact: Mary Hightower, (501) 671-2126, mhightower@uaex.edu
