New guidebook highlights key to spraying efficiency

A NEW technical and troubleshooting resource for grain growers is available in the form of a Grains Research and Development Corporation guidebook for mixing and batching agricultural chemicals.

The guidebook is a key outcome of a four-year GRDC extension investment into spray efficiency and efficacy, which also included hands-on sprayer calibration and application workshops for growers.

The guidebook showcases day-to-day practicalities, with grower case studies for various enterprise sizes, each bringing different concepts, ideas and creative engineering to spray operations.

For Phil and Tom Longmire, who crop 5700 hectares near Esperance, Western Australia, over six adjoining properties, spraying operations are logistically complex.

“Timeliness of spray operations is critical for their success, and this is contingent on the capacity you have available — both labour and equipment,” Mr Longmire said.

“We have upgraded our spray equipment over the years, customising it to the area of crop we need to service, but probably the key efficiency gain is how we use our limited labour source, particularly for mixing and batching chemicals.”

The Longmires use a tag-team approach to allow for the pre-batching of chemical granules and dry product for the next spray operator.

This means products have time to dissolve and can be pumped straight into the spray units.

“Each year we spray around 40,000 hectares,” Mr Longmire said.

“When spraying, on average we cover 1000ha per day, which equates to five to six spray tank loads per day.”

The case studies included in the guidebook cover a range of operation sizes (both grower and contractor) and crop mixes in different rainfall zones.

They explore the individual requirements – such as farm infrastructure, equipment and staff management – required to service their spray operations.

Aspects to consider to identify efficiency gains for mixing and batching agricultural chemicals include water availability, labour availability, farm size and layout, spray units, size and number of units to suit farm conditions, mobility of the units, ease of decontamination and occupational health and safety.

The guide can be found at https://grdc.com.au/resources-and-publications/all-publications/publications/2022/mixing-and-batching-agricultural-chemical-application-grower-case-studies