If you've ever opened a bag of pet food or box of cereal to find crawling beetles, flying moths or webbing, you know the unpleasant experience of having found stored product pests, or pantry pests. The best way to avoid such an experience is to prevent the pests from infesting your foods and inspecting bagged and boxed food items you bring into your home.
Beetles and Moths
While there is only one moth, the Indianmeal moth, that commonly infests stored food, there are a number of beetles that may infest the boxed or bagged foods in your pantry or cabinets. The most common are the warehouse beetle, sawtoothed grain beetle, merchant grain beetle, confused flour beetle, red flour beetle, drugstore beetle, and cigarette beetle.
Pantry pests are generally brought into your home in an infested food. But because they are so small, you will often not know they're there until the population has grown into a major infestation.
The most common signs of an infestation are the actual pests - tiny beetles, flying moths, tiny light-colored worm-like larvae or eggs. You may also see signs such as spun webbing through the food and on packaging, which the larvae trail and spin as they feed and crawl.
Note, however, if you are seeing a tiny moth, of about ¼ inch long, or webbing in or around clothing, it is more likely to be an infestation of clothes moths.
Pantry Pest Control
If you have found any of these signs in your home, your first thought may be to call in a professional, but because control of these pests revolves around finding and ridding your home of the source, it can be as effective to do it yourself in 3 basic steps:
Find the source.
Check all foods in the area in which you are seeing the beetles or moths. Check for signs of damage to or webbing on the packaging, and for live or dead beetles, moths or larva in and around the food. If you find a food with any of these signs, carefully check all food in the area.
Stop the infestation.
All food with any evidence of any pest presence must be:
- discarded and immediately taken from the home; or
- placed in the freezer for 3 to 4 days to kill all stages of the pest and its eggs; or
- heated in an oven at 140° for one hour for complete kill.
Clean the area.
- Remove all foods, infested or not, and thoroughly vacuum the entire area, taking care to get into corners and along back and side walls. Empty and clean vacuum canister and discard bag outside the home to prevent re-infestation.
- If the infestation is severe, you may need to call in a professional, who will thoroughly inspect and (once food is removed) apply any needed insecticide. If you do decide to call in a professional, be prepared to tell the technician where you found the pests or evidence and expect to remove and/or discard foods and clean the area prior to restocking your pantry.
To prevent pantry pests:
- When purchasing any bagged or boxed food, especially pet foods and birdseed, check package for damage or pest evidence, and ensure seals are intact.
- If you have any doubt, open package outside or place in freezer for 3 or 4 days before opening. Instead of stocking up on susceptible items, such as flour and milled products, buy smaller packages that will be consumed within a few months.
- Repackage susceptible items, or those you will not use in a short time, in pest-proof glass or metal or thick plastic containers.
- Keep pantry and stored food areas clean, sweeping, vacuuming and/or mopping regularly to prevent build up of spilled foods.
- If you do see any sign of these pests, act as soon as possible to keep the infestation from spreading, reduce the need for food disposal and decrease the need for chemical control.