Trials with Monsoon herbicide against a range of broadleaf weeds, including this volunteer cotton site on the Darling Downs in Queensland, have demonstrated its effectiveness, in this case applied at 1 litre per hectare in a tank mix with 1.6L/ha of Wipe-Out Pro, as well as Hasten at 1%.
Northern croppers have a lot to think about when applying broadleaf herbicides on winter and summer fallows.
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From the herbicide’s effectiveness on weeds, plantback intervals, one-pass applications with brews containing grass herbicides and any related antagonism, volatility and application restrictions in sensitive cropping areas; and, also weather conditions after spraying.
Fortunately, increased uptake of a dual mode of action broadleaf herbicide, including for the popular optical spot spraying of winter and summer fallow weeds, has simplified the decision-making for growers in their summer cropping programs.
Monsoon, developed by ADAMA Australia, is a co-formulation of two proven active ingredients, bromoxynil (Group 6) and fluroxypyr (Group 4), and it has demonstrated excellent control of a wide range of difficult broadleaf weeds, vines and woody weeds.
It also can be combined with a range of compatible tank-mix partners, with minimal impact on the efficacy of grass herbicides and without the volatility concerns or re-cropping limitations of some alternative options.
Market development manager with ADAMA Australia in Southern Queensland, Jim O’Connor, said trials with Monsoon in Northern New South Wales and the Darling Downs region in Queensland had shown strong activity on volunteer cotton, fleabane and saltbush, and it had been ideal for weed control programs with optical spot sprayers.
Mr O’Connor said Monsoon was attractive to cotton growers due to its excellent activity on genetically modified cotton volunteers and a range of hard-to-control weeds. Monsoon can be successfully tank-mixed with grass control partners such as glyphosate, glufosinate and Group 1 chemistry for robust control of susceptible summer grass weeds at early growth stages.
“There can be some antagonism when using Group 4 chemistry with grass control herbicides, however it is reduced when using fluroxypyr in combination with bromoxynil, especially at lower use rates,” Mr O’Connor said.
There is also reduced carryover risk associated with these active ingredients, with the re-cropping periods following Monsoon application set at seven days through to 28 days according to application rate and rotation crop type.
“It has a nice rate range with optical spot sprayers up to 4 litres per hectare, so growers can go with a high dose if needed or use a lower rate to further reduce the re-cropping interval,” he said.
“In addition to volunteer cotton and fleabane, Monsoon helps target hard-to-control broadleaf weeds on summer fallows using optical spot sprayers, and it is ideal in areas where there are use restrictions on 2,4-D herbicides, including where there are summer plantings of cotton and other crops like grapevines and tree crops. However, growers still need to employ excellent spray application practices.”
He said the combination of the two active ingredients also had demonstrated success against saltbush, sowthistle and ipomoea vine species, while bromoxynil (Group 6) chemistry was not often used on northern fallows, which helped to maximise herbicide efficacy.
“It has allowed a different chemical group to come into fallow programs,” he said.
“Monsoon applications are also robust in a range of suitable meteorological conditions, whereas alternative herbicide efficacy can vary depending upon conditions.”
Mr O’Connor said growers were having to decide over the use of traditional herbicides, different brews and various products under permit with their fallow weed control applications, so the registered use of Monsoon with optical spot sprayers is a great benefit.
Monsoon also can be applied in winter cereals, targeting broadleaf weeds in post-emergent applications.
For further information on Monsoon herbicide applications in fallows and winter cereals, growers and advisers can contact their local ADAMA Australia representative.
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Caption: Trials with Monsoon herbicide against a range of broadleaf weeds, including this volunteer cotton site on the Darling Downs in Queensland, have demonstrated its effectiveness, in this case applied at 1 litre per hectare in a tank mix with 1.6L/ha of Wipe-Out Pro, as well as Hasten at 1%.
Some of the untreated volunteer cotton at the Darling Downs trial site in Queensland.
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Caption: Some of the untreated volunteer cotton at the Darling Downs trial site in Queensland.
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