Herbicide resistance is a growing area of concern in Australian farming systems.
Weed management is complex, and trying to maintain a balance between resistance, control achieved and expenses can be challenging. BCG is carrying out research and extension around the adoption and agronomic use of shielded sprayers in the Wimmera and Mallee. This includes a trial which aims to provide a breakdown of shielded sprayer effectiveness and economics of use in a problem ryegrass paddock.
Kinnabulla grower Lincoln Lehmann came up with a “crazy idea” several years back while facing the challenge of brome grass control and getting frustrated with group B products.
“It was getting to a stage where you’d base your rotation around weed control rather than the most profitable option,” Mr Lehmann explained.
Mr Lehmann runs a 2300ha continuous cropping property with his parents and grows wheat, barley, canola, field peas and lentils. He found brome grass was starting to become a problem and started looking at a novel way to tackle it. After a lot of time testing smaller versions behind the motorbike and around a month in the workshop, he came up with the first version of his shielded sprayer.
“I was shocked with how well it worked.”
The first year he mostly targeted problem patches, but since then he’s done whole paddocks and, in the last few years, estimates he’s covered between 15-30 per cent of the property each year.
Mr Lehmann only uses his shielded sprayer in cereals as they are able to guide the shields between the crop rows. Varieties with erect growth habits work best; it works well in wheat and upright barley varieties like Spartacus and Hindmarsh. He has predominately used paraquat, but finds glyphosate to work well too.
Timing is the most important factor in reducing crop damage. Generally, yield is unaffected when it’s used “in the right crop at the right time.”
BCG will be extending information from this project.