News

Biosecurity risks with a wet harvest!

08 Dec 2022

By Shafiya Hussein, Grains Biosecurity Officer, South Australia

Australia is experiencing one of the wettest seasons in many years, with the third successive year in a La Nina cycle (a naturally occurring climatic event). As a result, grain producers are experiencing wet soil (mud), full rivers and dams, isolated flooding, and the threat of a wet harvest.

This year’s wet season has seen an explosion of weeds harbouring pests and diseases. Extra vigilance is needed to reduce the impact on grain crops. The introduction and dispersal of pests can reduce farm profitability by:

  • reduction in yield and product quality
  • increased costs for management and control
  • rejections at receival depots
  • trade restrictions

The Grains Farm Biosecurity Program (GFBP) aims to support management practices designed to prevent, minimise, and control the introduction, spread and distribution of pests such as weeds, insects, nematodes, molluscs, bacteria, fungi, and viruses. Early detection through continuous monitoring and surveillance is critical.

Biosecurity safe at harvest

At harvest, there is a considerable increase in on-farm activities with the movement of workers, equipment, and machinery. This movement corresponds to a rise in biosecurity risks on-farm. The following points reduce the risk and prepare growers to be biosecure:

  • Clean, dry, and disinfect grain silos and other storage facilities before harvest. Insect protectants such as DryacideTM a non-toxic verified structural treatment for grain storage facilities. It is effective against weevils, beetles, borers, and moths
  • Check the moisture of grains at harvest or have a grain dryer to ensure grain moisture is within limitations (check with your agronomist for each crop) for storage. This minimises mould growth, quality degradation and insect damage
  • Provide signage and designated parking zones for all visitors to your property to minimise the introduction and potential spread of new weeds and other pests
  • Farm managers should provide designated pathways for incoming produce haulage trucks and loaders. This reduces the risk of pest spread to other regions of the farm
  • Ensure that all contract harvest equipment and machinery is cleaned thoroughly and checked for grain, weed and soil remnants before entering the property. In muddy conditions, tractors and harvesters can accumulate up to 300kg of soil which can carry invasive weed seeds, rust spores, nematodes, and other pest invertebrates
  • Thoroughly wash, rinse, and dry all plant trimming and pruning gear before moving into the next paddock
  • Wash equipment with compressed air and water and finally with a disinfectant to remove 99.9% of inert or possibly infected matter. Leaving disinfectants on equipment and machinery for 30mins is most effective
  • Always harvest clean paddocks first, then move machinery into paddocks containing weeds or livestock last
  • All visitors, contractors, agronomists, and workers on farm paddocks should wear protective gear and have disinfectant/wash areas available to remove soil and debris from clothing and footwear before leaving the property. A diluted bleach solution or any recommended APVMA-approved disinfectant in a trough or tub to cover the soles of boots will suffice.