Applying yourself to new 2,4-D regulations

Changes to 2,4-D use regulations are in the grain industry's best interests


Agronomy
The latest GRDC Nozzle Selection Guide to help growers meet the new 2,4-D regulations. A chart for Pulse Width Modulation (PWM) systems is also available. SOURCE GRDC

The latest GRDC Nozzle Selection Guide to help growers meet the new 2,4-D regulations. A chart for Pulse Width Modulation (PWM) systems is also available. SOURCE GRDC

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New 2,4-D application requirements to prevent off-target herbicide damage and contamination.

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Key points

  • All products at point of sale will have either a new compliant label, or a 'Product Specific Spray Guidelines' brochure, or the vendor will provide a copy of the permit
  • Very coarse (VC) or coarser spray quality will require an application volume of between 80 to 100 litres/hectare to maintain spray coverage and weed control. Downwind buffer zones will vary with 2,4-D products
  • Additional APVMA permits with specific guidelines for use with 2,4-D include: PER87570 allowing for the use of optical spot spray technology; PER87451 allowing for aerial application; and PER87338 boom heights up to a maximum 0.85 metres from the ground.

In October 2018, the Australian Pesticides and Veterinary Medicines Authority (APVMA) suspended all 2,4-D labels following the 2,4-D Environmental Assessment Report. The aim was to ensure all products containing 2,4-D continued to be used in a manner safe to the environment and agriculture. The suspended labels were replaced with an APVMA permit (Permit 87174), which outlined the new application requirements for any product containing 2,4-D.

These changes affected more than 200 products. The instructions for use include:

  • not spraying when surface temperature inversion conditions exist;
  • a requirement to use nozzles producing droplets no smaller than very coarse spray quality;
  • advisory statements about spray application over summer to use extremely coarse (XC) to ultra coarse (UC) spray quality in sensitive areas;
  • downwind mandatory no-spray zones for both aquatic and terrestrial off-target vegetation (including sensitive crops, gardens, landscaping vegetation, protected native vegetation or protected animal habitat); and
  • mandatory record-keeping requirements.

The new instructions do not change or restrict other aspects of the currently approved use patterns for 2,4-D.

To meet the new 2,4-D use requirements, many grain growers will need to invest in another set of nozzles.

For 2,4-D manufactured and labelled before the suspension, suppliers must either provide the new instructions to the purchaser or attach them to containers. Some chemical suppliers have updated their labels with the new instructions while others are supplying 2,4-D formulation-specific spray drift guidelines to supersede old labels.

Three additional permits are available for optical spot spray technology (OSST), large booms and aerial application of 2,4-D.

Permit for optical spot spray technology (PER87570) using 2,4-D

Nufarm® has obtained a permit to allow the use of Nufarm Amicide Advance 700 Selective Herbicide and Trooper 75-D Herbicide to be used with OSST such as the WEED-it™ and WeedSeeker™ units. Mandatory conditions include:

  • spray droplets not smaller than a coarse (C) spray quality;
  • a maximum boom height of 75 centimetres above the ground; and
  • weed coverage no greater than 10 per cent.

Permit for large booms - boom heights up to a maximum 0.85 metres (PER87338)

Nufarm® has obtained a permit for the use of their products containing 2,4-D when used through large booms that cannot deliver the minimum 0.5m height above the target. Mandatory conditions include:

  • using a spray quality not smaller than ultra coarse (UC); and
  • a maximum boom height above target of 0.85m.

Permit for aerial application of 2,4-D (PER87451)

General permit for 2,4-D products previously registered for aerial use. Mandatory condition is to use a spray quality not smaller than very coarse (VC).

See the permit for how this is calculated with different aircraft and equipment.

Selecting the correct nozzle

To meet the new 2,4-D use requirements, many grain growers will need to invest in another set of nozzles as all pre-orifice and most low-pressure air induction nozzles cannot produce very coarse (VC) spray quality at workable pressures and flow rates.

Follow the links below to the GRDC Nozzle Selection guides for conventional spray systems and Pulse Width Modulation sprayers to select the correct nozzles for your situation.

GRDC 2019 Nozzle guide - Conventional spray systems

GRDC 2019 Pulse Width Modulation Nozzle Guide - for example, AIM Command™, JD ExactApply™, Agrifac™

More information: APVMA Special 2,4-D Gazette, https://apvma.gov.au/node/32951

New APVMA 2,4-D Permit, https://apvma.gov.au/node/15581

GRDC Spray Drift information

GRDC Maintaining Efficacy With Larger Droplets - New 2,4-D Application Requirements Fact Sheet

Nufarm Optical Spray Spot Technology Fact Sheet, https://cdn.nufarm.com/wp-content/uploads/sites/22/2018/05/06182547/TNOSST-2016OpticalSpotSprayTechnologyRegistrationsForHerbicides-Print_V1.pdf

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