Stored Product Pests

Stored products can be infested at every point from their origin to final use in:

  • The field, where the product is grown, picked, or harvested.
  • Storage bins or granaries, where it is held until sale
  • Mills, where it is ground, mixed, or packaged.
  • Warehouses, where it is held for use or redistribution.
  • Food processing plants, where it is added to other products (eg., candy, pet food, baking mixes).
  • Food serving establishments, where it is prepared for public consumption
  • Retail food stores, where it is sold.
  • Pantries and cupboards, where it is held for use.

The most commonly attacked products are cereal, grain , spices and nuts. Less commonly attacked are dried fruit, candy, rodent bait, dried dog food, dried decorative flowers and such diverse materials as museum artifacts, cosmetics, and drugs. Old, neglected, or hard-to-reach products pro-vide the greatest potential for infestation and reinfestation.

Control and Management



In large facilities, a pest control applicator will want to become familiar with the entire operation before making an inspection. The pathway a product takes is vitally important to detection. Pests can occur in machinery, stacked products, waste dumps, delivery spills, etc. In homes and retail businesses, excess clutter, bad lighting, storage areas with blocked access, and rooms located above or below infested materials are special target sites.

  • All inspections should be conducted with strong flash-lights.
  • A knife, a good hand lens, screwdrivers and mirrors are also useful equipment.
  • Flushing agents can be used, but care must be taken not to contaminate foodstuffs.
  • Special attention should be given to all spills. Check for pests, cast skins, and tracks in spilled products or dust.
  • Inspect the back of pantry shelves, floors under shelves, and all dark areas.
  • Pheromone traps, available for nearly all stored product pests, should be used where routine inspections are made.
  • Keep detailed inspection records. Written inspection findings and recommendations for changes by management or maintenance must be clear.
  • Work safely. Use hard hats and be careful of heat machines,and electrical hazards.



  • Institute a good ongoing cleaning program. Pesticides used without cleaning will not stored product pest infestations.
  • Caulk cracks (especially wall penetrations) that communicate with other rooms
  • Screen out birds and rodents.
  • Recommend good lighting.
  • Point out areas that need ventilation.
  • Recommend reduction of clutter and excess product in cabinets or storage.
  • Collect and discard old rodent bait.
  • Maintain alleys or inspection paths between stacks of products and between products and walls. (Have them painted a light colour)
  • Install air curtains at doors to keep out flying insects
  • Recommend rotating stock.
  • Recommend storing materials that are not commonly infested (e.g., animal bedding, paper products, canned goods) away from infestible products.
  • Discard infested materials. (Sanitation is the primary method of population reduction where infested stored products are found).

Pesticide Application


  • Pesticides registered for use in the infested area should be carefully applied to cracks and crevices.
  • Apply spot treatments only in areas where there is an obvious and immediate need to control migrating insects.
  • Install insect electrocuters properly to attract flying in-sects.
  • Investigate pheromone trapping for killing in conjunction with other methods.


Ongoing monitoring and inspection plans should be put into effect in all food handling Establishments. A complete pest management program is recommended for these operations. Recommendations on cleaning and sanitation should be evaluated continuously.