Corteva Agriscience has long recognised the benefits and strengths of 2,4-D herbicide. With its robust broad-spectrum activity on some of the most important hard to kill weeds, it is well justified as a vital tool for fallow management.
However, for many farmers, the use of current 2,4-D products is becoming increasingly difficult to maintain due to the proximity of 2,4-D sensitive crops and restricted use areas.
Colex-D is a next generation, patented technology developed by Corteva with the drift management refined through a collaboration between Corteva and several North American Universities dating back to 2007.
Colex-D product manager Guy Sands said Colex-D is a Novel form of 2,4-D which offers all the performance and efficacy of traditional 2,4-D products, but has field proven drift reduction technology (DRT), Near-Zero volatility and Ultra-low odour built in.
“Colex-D is an ideal option in Australia because it allows farmers to take advantage of the robust weed control 2,4-D is known for, while significantly reducing off-target movement that has been a problem with older 2,4-D formulations.
“The proprietary drift reduction technology in the Colex-D formulation is designed to eliminate droplets at the finer end of the spectrum and generate more optimally-sized droplets.
“This maximises product performance and minimises the risk of off-target movement,” Mr Sands said. “When Colex-D is applied according to the label, it offers an improved droplet spectrum which ensures the herbicide reaches the target weed.”
Mr Sands said Colex-D and many common tank-mix partners have undergone extensive wind tunnel testing to establish performance standards using a range of nozzle combinations common in Australia.
“It is important to test the droplet spectrum when mixed with tank mix partners as these combinations alter the range of droplet size, sometimes not for the better. In some cases, mix partners did not pass our rigorous testing and will not be supported on the label.”
The Colex-D label contains application advice for a wide range of different nozzle types and operating pressures to ensure the product advantages are maximised. Corteva has thoroughly tested the labelled mix partners to ensure physical compatibility and field efficacy in Australian conditions.
Mr Sands said the challenges of volatility, where the compound moves from the treated area after application, have also been addressed with the unique Colex-D formulation.
“While traditional 2,4-D amine formulations break apart in the spray tank resulting in more volatile components, the novel choline salt in Colex-D stays associated and is much more stable in the spray solution and on the sprayed surfaces following application.”
Corteva trials demonstrate that this novel choline salt formulation reduces 2,4-D losses due to volatility by more than 86% when compared with the amine salt form.
Testing has shown that 2,4-D amine can volatilise from a sprayed surface 12 hours after application. Mr Sands said applying Colex-D gives farmers greater confidence that the risk of off-target movement and potential damage is reduced after spraying.
“Additionally, the patented formulation and refined manufacturing process of Colex-D has produced an ultra-low odour product making mixing, handling and application a more pleasant experience for the applicator and the community.
“Colex-D is an exciting development for Australian agriculture and addresses many of the major concerns associated with traditional 2,4-D products.
“Colex-D is a novel choline salt formulation of 2,4-D that allows farmers with proximity to 2,4-D sensitive crops, to access the robust weed control of 2,4-D with reduced risk of off-target damage.
“The built in Drift Reduction Technology, Near-Zero volatility and Ultra-low odour means Colex-D is a 2,4-D that can be applied with confidence,” he said.
