Pest Control Pest Library Weevils, Beatles, Moths, Borers
Weevils, Beetles, Moths, Borers
A “pest of stored products” can refer to any organism that infests and damages stored food. While stored products can include a variety of materials, the major concern is with pests that destroy food and food products
Of significant importance are ;
- Beetles (Tribolium spp)
- Weevils (Sitophilus spp)
Weevils (Sitophilus spp) Rice Weevil
Small dark brown, reddish-brown or black elongated weevils, about 1/16 inch in length. The most prominent distinguishing feature is the pronounced snout projecting in front of the head.
Heavy infestation causes the stored grains to heat up, resulting in mould growth and change in flavour and taste. They can chew through plastic and paper bags to reach stored food.
Beetles (Tribolium spp) Flour Beetle
Small, slender, flattened and elongated, reddish-brown beetles, about ⅛ inch in length. Do not usually damage whole grains, but found more in broken bits and flour, or grain previously infested by other pests. The damage is less due to feeding, but more due to contamination of the stored product with large numbers of various life stages, dead bodies, cast skins, and faecal pellets.
How to reduce infestation
- Grain handling equipment should be kept clean
- Store only clean, dry grain. A small percentage difference in moisture content can make a big difference in the probability of a damaging insect infestation.
- once an insect infestation has become established, there are only two treatment options: (1) move the grain and apply a protectant during transfer or (2) fumigation
Quality assurance tip
Always ask your pest control provider to provide an integrated pest management (IPM) plan for your property.
Health and Safety tip
Stored grain insect infestations rarely begin in the field. Most develop from small numbers of pests already present in or around farm storage areas. An effective sanitation program can eliminate or greatly reduce the chance of having serious problems with these insects
Grain aeration, temperature and moisture control, routine turning of grain can be done to control these pests.
Commercial pest control is regulated by Ministry of Agriculture, Animal Industry & Fisheries (MAAIF) and all pest controllers must have a license issued by MAAIF. Even though public health pest control is not regulated yet, MAAIF license may suffice.
- Adult rice weevils are able to fly and can live for up to two years. Females lay 2-6 eggs per day and up to 300 over their lifetime. The female uses strong mandibles to chew a hole into a grain kernel after which she deposits a single egg within the hole, sealing it with secretions from her ovipositor.
- Rice weevils in all stages of development can be killed by freezing infected food below 0 °C for three days, or heating to 60 °C (140 °F) for 15 minutes.
- Adult beetles rarely fly and feed very little during their short lifespan of about 14-30 days. Eggs are laid loosely in the food source and the hatching larvae immediately begin to feed.
- While the beetles are not particularly good at penetrating through packaging material, they are adept at invading through small cracks and gaps in package seals and able to pass through holes 1.2 mm in diameter