Queensland farmers experiencing crop losses from the aggressive and ravenous fall armyworm are facing what a senior entomologist has called, "unprecedented" damage.
Four years after first being detected in Australia, FAW has spread to all grain-growing areas across Queensland.
A research project funded in part by the Grains Research and Development Corporation has experts from the Queensland Department of Agriculture and Fisheries in conjunction with the University of Queensland to find a way to sustainably and economically manage FAW.
DAF principal entomologist Dr Melina Miles is working with Dr Joe Eyre from UQ's Queensland Alliance for Agriculture and Food Innovation. on field trials in maize and sorghum at DAF research stations at Gatton and Ayr.
Recent damage to crops had been the "worst experienced" since the pest landed in 2020, Dr Miles said.
Dr Miles said FAW was known to have impacted sorghum and maize crops in all the regions where these crops are grown, including from Mareeba, Atherton, the Burdekin, Central Queensland, Burnett, Darling Downs, Lockyer and Fassifern Valleys, McIntyre and south of the border as far as Gunnedah.
"DAF are taking this very seriously and have committed $3.8 million over the last four years," she said.
"This year we have levels of damage not seen in the previous two years and growers and agronomists are calling to talk about their particle scenario and their particular risks.
"I have spoken with close to 30 agronomists and 10 growers and they are very concerned as to what happens from here on."
Dr Miles and Dr Eyre said part of their research involved understanding the relationship between the timing of a FAW infestation, its density and the crop's response to canopy damage and potential yield loss to be able to guide growers to make economic decisions on treatment.
"These trials have provided valuable data as we haven't had a severe defoliating pest before, and most producers haven't had to worry about insect pests before flowering," Dr Miles said.
"Australia's grains industry is used to having economic thresholds on which to base decisions about the need for, and timing of, pest management and farmers are crying out for guidance because fall armyworm is so damaging and unfamiliar."
Dr Eyre said while FAW is immensely challenging, growers should not give up hope.
"We advise growers to be alert and be aware but FAW is manageable, not all infestations require control," he said.
"Initial observations demonstrate quantifying the size of FAW infestation and identifying the crop development stage is critical to effective management.
"Ongoing research will establish these critical thresholds.
"We need to understand how FAW infestation of crops already stressed from water or nitrogen and short-term forecasts impact the return on investment for FAW control."
The trials are co-funded by DAF and a $750,000 investment from the Grains Research and Development Corporation.
GRDC Biosecurity manager Callum Fletcher said the organisation contributed $750,000 towards the trials.
"GRDC recognised FAW as a significant and ongoing threat," he said.
"We are continuing to invest to ensure they have the best tools, technologies and information to sustainably and effectively manage FAW going forward."
Grain grower John Crothers who farms wheat, barley, chickpeas, sorghum and corn north of Dalby, said FAW numbers had increased.
"In the past three years has accelerated in numbers," he said.
"This season we are up to five sprays so far compared to last season we did three."
Pulse Australia and WeedsSmart industry development agronomist Paul McIntosh said growers were "extremely concerned" about FAW impacting crops, especially maize, grain and forage sorghums and millet.
"This year the rain and humidity has helped create a really big infestation, this is the first big year grain sorghum in southern and Central Queensland has been impacted and growers are alarmed," he said.
"At the moment grain sorghum is around $350 a tonne and no-one wants to lose yield due to FAW.
"Everyone really appreciates the research Dr Miles and Dr Eyre are doing."
Nutrien Dalby agronomist Ross Pomroy said growers in the Western Downs were under "high pressure" from FAW.
"FAW is primarily impacting corn planted in December but now it's moved on millet crops as well as sorghum," he said.
"I believe if we hadn't sprayed then we would 100 per cent not have a crop."
Mr Pomroy said crops in his region were being sprayed "four or five times," but he understood some northern growers had sprayed, "up to nine times," in an attempt to eradicate FAW.
"The rain's been good but it means we had to apply the most recent control by plane which is not as effective as by ground rig," he said.
"Into the future we are very concerned about planting sorghum or corn in the late planting windows and cost of control."
Know more about this issue? Contact Alison Paterson on 0437 861 082.
