Physical control of grain insect pests
In the past, grain dryers have been used to help with disinfestation. There are a number of variables that are difficult to manage and may affect end use quality of grain, including temperature, time, and type of dryer. As a result, insect control using high temperature may produce variable results.
Caution: After you apply heat treatment, grain must be immediately cooled so that it does not overheat, spoil and cause a new insect infestation. Energy costs for this method of control are high. Therefore, using a grain dryer is recommended only when you need to rapidly dry grain.
Producers and grain handlers can use ambient cold air to prevent and control infestations.
Stored product insect pests generally do not feed or reproduce at temperatures below 18°C. Lower temperatures can also be used to cause mortality. For example, grain kept at -5°C for 12 weeks will control stored insect pests at all life stages.
You can lower the temperature of stored grain by:
- Mixing and transferring infested grain from one bin or pile to another
- Transferring part of the crop to a truck or small pile to expose it to low air temperature and leaving it to cool before returning it to the bin
- Aerating the bin
Aeration systems are very effective at reducing grain temperatures, as well as reducing moisture migration.
|Constant grain temperature
|Time period required for disinfestation
Cyclone-based grain pneumatic conveyers (also called pneumatic grain auguers or grain vacs) can control insect infestations. The percussion effect created by the cyclone causes insect mortality. The style of pneumatic conveyer and the class and physical condition of the grain may affect this method of insect control. High grain volumes can reduce the effectiveness of this method of control.
- Date modified: