With the 2025 harvest on the horizon, farmers are being advised to prioritise thorough grain store hygiene to reduce the risk of costly insect infestations.
Mild winters are no longer providing the natural pest suppression once afforded by colder weather, according to pest expert Ken Black, of Envu.
“We’re no longer benefitting from the cold winter air that helped lower temperatures in grain stores, and in turn, help keep insect numbers down."
He cautions that despite the time and investment farmers put into growing high-quality crops, poor preparation of storage facilities can lead to losses that rival damage caused by pests in the field.
“If you don’t get the storage environment as clean and insect-free as possible, you risk undoing all that effort,” he explains.
“Grain storage preparation is often the missing piece of the growing season jigsaw, but insect damage in stores can result in losses comparable to pests and diseases in the field.”
Mr Black recommends starting the cleaning process six to eight weeks ahead of harvest. However, he notes that market conditions — such as high grain prices — can shorten that window.
“A common mistake is only cleaning the floor and walls. It’s essential to get right up into the roof space, underfloor areas, drying ducts, conveyors, elevators, handling equipment, and even the combine — these are all places where insects can live.”
Once the cleaning is complete and debris removed, Mr Black suggests placing traps to monitor insect presence, checking them after seven to ten days.
“On the very rare occasion that no insect activity is found, a decision can be made to skip chemical treatment. But in most cases, farmers will apply a treatment as a belt and braces approach,” he explains.
Mr Black stresses that any treatment must be thoroughly applied and left long enough to work.
“It takes at least 24 hours to kill adult insects. However, the lifecycle of some insects is longer, so additional time is needed for them to emerge and come into contact with the product."
Adopting a proactive approach to insect control, rather than a reactive approach, really pays off, he adds.
“You don’t want to be left in a position where you’ve cleaned the store but missed a few insects, because if you haven’t sprayed against them, they’ll descend on the new grain once you put it in the shed and you’ll fall foul of a costly infestation.”
