Some observations on storage insects associated with sacks.
The following is virtually the author's summary. Infestations of empty food sacks by stored-products insects were studied by examination of 350 sacks during a period of 7 months. These sacks had been used for the storage and packing of flour, meals and grain in south-west England and in Wales. The observations were made during investigations following the rapid reinfestation of buildings by insects thought to be introduced on returned sacks. They showed that the insects occurring in the sacks belonged to three habitat groups, comprising those associated with flour mills in moderate climates, those associated with grain, and general feeders. Infestation was found on 25% of the returned flour sacks and 29% of general sacks. Oryzaephilus surinamensis (L.) occurred inside sack bundles, usually consisting of nine sacks inside a tenth, where it was associated with flour-mill insects. Factors involved in the occurrence and spread of insects are considered in relation to the data available from the investigation.