With a number of weeks of warm weather this summer, growers are encouraged to check their grain in storage more regularly.
A regular check including taking a sample form the head-space and the bottom of the silo to screen for insects is recommended at least monthly.
But in warmer weather, growers should double-down efforts and check silos every fortnight because insects thrive in warm conditions and can multiply rapidly.
Research conducted by the GRDC extension team found that temperatures in silo headspaces could approach 60° Celsius. This warms grain in the headspace, making it more favourable for insect activity including more rapid reproduction.
Around half a bucket-full of grain should be taken from both the headspace and base for sampling with the headspace sample extracting grain from around 300mm below the surface.
Shaking the grain over a 2mm sieve should see any insects present fall through the screen.
Alternatively, insect traps left in the grain can be used to capture insects and retain them. The grain traps should be checked and re-set each time the grain in storage is checked.
If insects are detected through the screens or in traps, a plan for eradication should be enacted with Phosphine being the most commonly utilised fumigant on farm in Australia.
But phosphine should only be used in a gas-tight sealable silo meeting the Australian Standard for sealing AS2628.
More information can be found in the GRDC Fact sheet “Vigilant Monitoring Protects Grain Assets”
Or watch the video of Peter Botta explain monitoring and insect identification.