Selecting nozzles to apply herbicides should primarily focus on reducing the risk of spray drift without compromising efficacy
Managing herbicide spray drift (continued from last issue)
Selecting nozzles to apply herbicides should primarily focus on reducing the risk of spray drift without compromising efficacy.
Drift (or loss) is a significant issue facing the industry and people applying herbicides have a moral and legal obligation to adopt current best practice.
Although there remains confusion among some growers regarding nozzle selection, the industry in general, backed largely by several years of trials on application rates, nozzle designs and travel speeds, generally agrees (and recommends) that growers can apply most herbicides with coarser spray quality without any detrimental effect on efficacy.
How coarse still depends on the herbicide, the target and the conditions at the time of spraying; and growers need to be prepared to adjust either application rate or nozzle design appropriately.
For example, if using very coarse droplets, higher water volumes might be required to maintain high levels of efficacy, particularly when targeting fine leaf grasses with grass selective (Group A) products.
Consult your spray equipment supplier for appropriate nozzle types and configuration.
More information on managing spray drift can be found on the APVMA website at https://apvma.gov.au/node/10796.
Download the Orchard plant protection guide 2020-21
See this article in Tree Fruit August 2021
