Applying contact graminicide Axial (pinoxaden) before GS30 of the crop is likely to give the most effective control of wild oats and save growers’ money, Rod Burke, Syngenta product manager, says.

But he recognises it isn’t always easy to know when spring germination has finished.

“You get the best control from spraying between GS25 and GS30 when all the weeds are up, and there is an open canopy,” he explains. Syngenta trials have identified Axial gives nearly 100% control in that situation.

Control drops to just over 90% from earlier applications, when late germination or problems hitting small weeds can be an issue, while control from post-GS30 applications is around 95%. “That’s when the bulk of wild oat sprays are made.”

Growers should be spraying now if they’re confident there won’t be any more germination, Mr Burke says, but identifying that is one of the major reasons for many delaying applications. “Wild oats aren’t the easiest to spot at this time of year,” he admits.

A pre-GS30 spray also allows the rate to be cut to 0.2 litres/ha, he points out. “It’s the best value option at that timing.”

New advice

Wild oats are usually paler than wheat, and typically the first leaf is very twisted in an anti-clockwise direction, Mr Burke says. “The ligules tend to be much larger than wheat or barley, and ragged.”

Syngenta has also issued new advice on which nozzle is best for different situations. At GS30-32 Axial is very effective at 100 litres/ha water volume, Mr Burke says. “The preferred nozzle is the Amistar nozzle, but it can also be applied through conventional VP03 or XR03 nozzles.

“But, for very high populations of wild oats or dense canopies, upping the water volume to 150-200 litres/ha through conventional nozzles has proved most effective in trials.

“In open crops or for early applications in spring barley angled nozzles provided the best control.”

Axial now comes in five- rather than one-litre packs following grower feedback, Mr Burke adds. “It was influencing choice away from Axial.”

Now, it is just one of the reasons to use Axial ahead of competitors Topik (clodinfop-propargyl) and Cheetah (fenoxaprop-P-ethyl), he suggests. “It means you will have fewer packs, less disposal costs, reduced down time between spray loads, as well as having one product which can be used for wheat and barley against wild oats and ryegrass.”

  • Spray before GS30 if possible
  • Rate can be reduced pre-GS30
  • Nozzle choice depends on situation