Chemical control

There are many approved chemical insecticides available for treating cracks and crevices or empty bins, including:

• Chlorpyrophos
• Diazinon
• Dichlorvos
• Dimethoate
• Malathion
• Pyrethrins
• Diatomaceous Earth

Note: Diatomaceous earth has the potential to reduce test weight. It is recommended to follow the instructions on the label, taking into consideration the auger flow rates when applying as diatomaceous earth increases friction.

Applying chemicals and fumigants to grain

Chemicals

Diatomaceous earth

• Can be applied directly to stored grain in Canada
• Method of physical control against infestations in stored grain
• Most effective when applied as dry grain is augered into a bin during harvest
• Treatment for a six-week period at temperatures at which insects can develop is necessary to ensure maximum efficacy

Malathion

• Incapacitates an insect by acting on its central nervous system
• Best applied as a liquid spray or dust as grain flows through an auger
• Intended for use on cereal grains. It is not registered for use on oilseeds.
• Grain treated with malathion should neither be sold for 7 days, nor used for feed until 60 days after application

Fumigants

Phosphine (PH₃)

• Usually applied as pellets or tablets to bulk grains either as the grain is entering the storage structure, or it is placed into the grain with a probe after the grain is stored
• Grain temperature and moisture are both factors contributing to the effectiveness of PH₃. Grain should not be fumigated if temperature is ≤ 5°C or if the moisture content is ≤10%
• PH₃ gas may react with certain metals (copper, brass, silver and gold) causing corrosion at high temperatures and humidity. Precautions should be taken to remove or protect equipment containing these metals, such as electrical motors, wiring and electronic systems.

Carbon Dioxide (CO₂)

• CO₂ is applied to grain as a gas from cylinders or as dry ice
• Structures must be well sealed in order to be effective
• Dose (maintain @ 60%)

ECO₂Fume (CO₂ + PH₃)

• New formulation of PH3 which has just been registered in Canada
• Gaseous PH₃ (compressed gas in a cylinder) which allows a more precise dosage of PH₃, faster fumigations, and fumigation at a slightly lower minimum temperature of 0°C, compared to that of PH₃ at 5°C.