Psocids

liposcelis bostrychophila

The white/grey/light brown coloured insects running around in your cupboards and on work surfaces are more than likely Psocids (pronounced So-sids) Often known as Book-lice. They are quite harmless, they are often found in the packaging of dry foodstuffs such as flour, dried milk, sugar, semolina etc. They feed on a wide variety of food products and also microscopic moulds that develop in humid conditions. They are also found in the spines of old books feeding on glue deposits and moulds, hence their common name.

Continue reading

Psocids prefer to live in dark warm humid places; the kitchen is an ideal environment. Fitted kitchen cupboards provide an excellent home for them and they will multiply quite happily there. They require a temperature of around 20o C to successfully reproduce.

Fresh flour contains some moisture and they will prefer this to previously opened packs and will migrate from old to new in a matter of hours.

Insecticidal control is difficult, but does eliminate the majority, but if the packaging remains, they will re-infest. It is also inadvisable to spray insecticides in any food storage cupboard or on food preparation areas.

Physical control methods include vacuuming the cupboards (do not wipe with damp cloths as this creates the moist conditions they need to thrive) empty the vacuum into an outside bin immediately after. Keep the cupboards cool and well ventilated and free from condensation and damp. When washing or cooking try to open a window to prevent condensation from building up.

Seal all potential hiding places in the cupboards and surrounding areas with mastic or similar, and paint over any unfinished edges. If food or food packaging is contaminated either dispose of it into the outside bin or place in plastic bags in the freezer for 24 hours, this will kill eggs and adults.

The other place they can hide is behind paper labels on tins, jars etc. you can write on the tin with felt pen the contents, then remove and destroy the label if they are found there.

All of the above will eventually eliminate the problem, and at little cost to yourself. You can also check Yellow Pages or similar and consult a pest control expert for a quotation, phone around for the best quote. For further information, if you have access to the internet search for Booklice or Psocids.