THE on-going plight, particularly of WA’s northern Wheatbelt farmers, over wild radish control is well known and Three Springs grower Chad Eva says management of the problem is getting worse, not better.
Chad and his wife Nadine continuously crop 6000 hectares to wheat, barley, canola and lupins on their property, Timuka, which comprises soils ranging from beautiful, soft red loams through to weak white sands.
The cropping program generally follows a lupin-wheat-canola-wheat or barley rotation.
Chad said while wild radish was less of a factor on their non-wetting country, it was their number one weed issue overall and was becoming a bigger problem.
“We are chasing it all-year-round – it comes in the summer as well,’’ Chad said.
“Last year we had green radish coming through in the barley leading into harvest.
“This year we had radish come up with the February rains and we didn’t get a good kill on some of it.
“We hit it with glyphosate and Sharpen herbicide at seeding.
“We normally would have gone with a phenoxy herbicide, but we thought we would probably use that in-crop.’’
Chad said he was facing another issue this season, with split crop germinations in paddocks likely to limit his herbicide application options.
“In the same paddock, there is wheat that is four-leaf, but the germination is patchy and there is also some crop that is just poking through,” he said.
“Split germinations like this limits our options as to what we can use in paddocks.
“When crops are at booting, it can limit the application of phenoxy herbicides.’’
Chad has successfully used the Group H post-emergent herbicide Velocity in recent seasons, sourced through Clayton Dennis at the local Landmark store.
As a result of the season, he said he would probably now use the product over almost everything.
“The window of application will be just so small,’’ Chad said.
He said they previously battled along with Tigrex and LVE MCPA herbicide mixes, with a sulfonylurea (SU) herbicide, but Velocity was much more flexible for early and late applications and offered excellent control, mainly of wild radish and also doublegee in some areas.
“It has been great,’’ he said.
“We have tried to hit radish twice – using Velocity first, which gets almost everything, and then the small stuff with Jaguar and a SU herbicide or Ester 680.
“It’s the only product that will take big radish down.’’
Clayton said with patches of tolerance to Group F herbicides increasing throughout the region, Velocity was becoming popular, particularly for cleaning up problem paddocks.
“It is being included in chemical rotations where needed, which is also helping to extend the use of existing chemistry,’’ Clayton said.
He said earlier applications of Velocity were favoured, but later applications were also successful.
Velocity is based on the novel active ingredient pyrasulfotole and also includes bromoxynil and Bayer’s crop safener, mefenpyr-diethyl.
The pyrasulfotole interrupts several biological processes crucial to weed growth, while the bromoxynil, which acts primarily as a contact foliar herbicide with virtually no soil residual activity, further disrupts the photosynthetic process, resulting in a unique action against weeds.
Chad said Bayer had been proactive in developing new herbicide modes of action and co-ordinating local trials, while backup support from the company’s customer advisory manager based in WA, Rick Horbury, also had been excellent.
To help further manage the weed seed bank, the Evas have been towing a chaff cart at harvest for the past four years and either burning chaff lines or leaving them to rot.
There has also been some crop-topping of canola, however those paddocks are normally almost free of weeds.
“Our canola and lupin paddocks last year were really clean and we were able to dry sow straight into them,’’ Chad said.
Meanwhile, net type net blotch in barley and sclerotinia disease in canola have been other major cropping problems for Chad and in recent seasons another Bayer product, the broadspectrum triazole fungicide, Prosaro 420 SC, has come to his aid.
“Net type net blotch has been a major disease and a nasty one – and it is worse in barley-on-barley. It can limit yield and you also end up with poor quality seed,’’ he said.
“I saved Prosaro for canola last year, but then I had to use it on the barley.
“We did one shot of Prosaro and then Amistar Xtra later.
“Prior to Prosaro we used flutriafol on the fertiliser, but it didn’t do a great job.’’
Chad said sclerotinia was “shocking’’ in his canola last season and they had to spray twice with Prosaro.
“We probably didn’t go as early as we needed to with the first spray and then we came back again,” he said.
“Prosaro is an awesome product for that – it is magic for ‘sclero’.”
Clayton said Prosaro was being widely used in cereal crops and canola across the region, although growers were mindful of rotating it with other fungicides to help protect the use of prothioconazole.