As crops begin to emerge growers are encouraged to be mindful when spraying, especially on paddocks with neighbouring crops and with glyphosate in the mix.
Spray drift incidences are becoming more prevalent and can have significant damage on crops as well as reputational risks to the industry.
Between mid-January and mid-February this year Biosecurity SA reported five cases in the Riverland and eight in the Clare Valley of off-target damage.
In 2017, a grape grower near Swan Hill was awarded $7 million in damages after spray drift of 2,4-D, glyphosate and metsulfuron-methyl caused significant damage to his vines in 2013.
Surface temperature inversion layers can be problematic in ensuring efficient and effective spray coverage and protecting emerged crops, hence the need to be particularly careful with spraying applications.
An inversion layer is where the air at ground level becomes cooler than air higher in the profile. Because cool air is denser than warm air, it remains at the surface. Therefore, sprays applied into this cool air layer can become trapped, allowing the droplets to then move in different directions depending on the general weather pattern.
The greatest risk for inversion layers are at dawn, dusk and during the night.
More information about inversion layers and effective spray application can be found in the GRDC fact sheet ‘surface temperature inversions and spraying’ and ‘GrowNotes – spray application manual for grain growers.’
To combat some of these concerns the Grains Research and Development Corporation (GRDC) is investing in upskilling and developing the knowledge of grain growers and industry about effective and targeted spraying techniques.
The new project, which BCG is leading is titled ‘Practical and applied workshops and communications to promote key messages and resources to maximise the effectiveness of spray applications in the southern region’. This project will see the delivery of 24 targeted workshops and communications across the GRDC southern region including South Australia, Victoria and Tasmania during 2018 and 2019.
BCG extension manager Ciara Cullen said it is excellent to see investment in this topic by our peak grains body given the reputational risk that off-target damage can have on the industry.
“The aim of the project is to reduce off-target spray damage, with particular interest in ensuring that different agricultural industries, e.g. horticulture and broadacre, can continue to work collectively within an area,” Ms Cullen explained.
For more information about the GRDC ‘Practical and applied workshops and communications to promote key messages and resources to maximise the effectiveness of spray applications in the southern region’ project phone BCG on 03 5492 2787.
This article was published in the Stock and Land on 31 May 2018.