New research from the GRDC Grain Storage Extension team has highlighted a safer and more effective way to apply diatomaceous earth (DE) in empty silos. DE, a fine dust made from fossilised aquatic organisms, is increasingly valued as a non-chemical pest control option, working by damaging the insect’s waxy coating and causing dehydration.
The study compared a standard compressed-air blower gun with an 18-volt battery leaf blower and a petrol-powered leaf blower, both fitted with Venturi attachments. Trials in a 6-metre cone-bottom silo and a 13.2-metre flat-bottom silo produced a surprising result. The compressor, long regarded as the standard approach, struggled to deliver DE evenly. In fact, in one trial, only about one per cent of the dust reached the top of the silo. By contrast, both types of leaf blowers provided consistent distribution throughout the storage, even from ground level, dramatically improving both efficiency and safety by eliminating the need for workers to climb.
An even bigger surprise came from the larger silo. Here, the petrol blower didn’t just cover more area—it kept the dust airborne longer, creating better circulation and far more uniform coverage. This suggests that in larger storages, more powerful blowers can actually improve performance, turning the traditional assumption on its head.
Safe and Sound
Before using or upgrading an ageing silo, growers should confirm that the foundation is stable with no cracks or tilting, that rust or corrosion has not weakened sheets and bolts, and that ladders, hatches, and safety rails are secure. A silo that passes these safety checks may still be fit for service. If not, replacement is the safest option.
According to GRDC extension officer Alex Conway, this finding is particularly significant. The study showed that “bigger is better” when it comes to ensuring DE is suspended long enough to reach all parts of large silos. It confirms that growers don’t need complex or risky methods to apply DE effectively—widely available leaf blowers with the right attachments can do the job, and do it safely.
This research demonstrates that a simple, low-cost tool can make DE application both safer and more effective, opening the way for broader adoption as part of integrated silo hygiene. With the right blower, growers can achieve thorough coverage, protect grain quality, and reduce reliance on chemical treatments.