Preventing off-target movement of pesticides

- Kay Amesbury, Biosecurity Queensland

Ongoing complaints about off-target movement of agricultural chemicals across property boundaries have prompted renewed calls for horticultural growers to ensure that all precautions are being taken to minimise the impacts of chemical application on people and the environment.

An industry led Responsible Chemical Use Working Group has been formed to provide a proactive, industry approach to address this problem.

The working group, assisted by Biosecurity Queensland officers, an agency within Queensland’s Department of Agriculture and Fisheries (DAF), consists of mango, avocado, sugarcane, banana and lychee industry representatives, chemical suppliers, agronomists, DAF horticultural extension personnel, local government and other government agencies.

Minimising off-target movement is an important part of using agricultural chemicals responsibly and Queensland’s agricultural chemical laws aim to reduce potential impacts on human and animal health, trade and the environment.

Be aware of your responsibilities as an ‘agricultural chemical user’

Under the Chemical Usage (Agricultural and Veterinary) Control Act 1988, growers could face large fines for failing to follow label instructions.

Biosecurity Queensland has provided the following tips to minimise the risks associated with off-target movement of agricultural chemicals:

Weather Conditions:

  • Avoid spraying when wind speed is less than 3 km/h during daylight hours and less than 11 km/h at night (a potential indication of the presence of a surface temperature inversion).
  • Thermal inversions can increase the potential for spray droplets, particularly fine droplets, to remain airborne for longer periods and therefore travel relatively large distances.
  • Avoid gusty conditions, wind speeds above 15 km/h or when wind is blowing towards a crop, livestock, dwelling or environment that can be damaged by chemicals.

Select right equipment:

  • Reduce spray pressure to the minimum required.
  • Ensure spray equipment (including nozzle) is appropriate, well maintained and calibrated.
  • Drop the height of the spray release as low as possible without interfering with the spray pattern. When spraying the canopy of perennial horticultural crops use equipment settings to direct droplets and prevent movement above the canopy.
  • Read the product label or permit and follow the instructions, particularly for spray quality (droplet size/spectrum), wind conditions, predicted rainfall events, application rate, total volume and downwind no-spray zones.
  • If you don’t understand a label or permit instruction, seek advice from a professional.

Be Aware of sensitive areas:

  • Growers need to identify in advance any sensitive situations, such as other crops, wetlands, water courses and residential housing within 1km and be aware of susceptible crops or sensitive areas.
  • Consider buffer zones between application sites and sensitive areas.
  • Consider your neighbours:
  • Develop a spray plan and discuss it with your neighbours and contractors.
  • Inform your neighbours of intended spray days.

For more information about responsible chemical use and spray drift minimisation, contact Biosecurity Queensland on 13 25 23 or visit www.biosecurity.qld.gov.au