Icy blow to southern yield

Agronomists say a significant frost on August 3 dealt the biggest blow.

Damage has now been reported in cereals, canola and lupins.

Weethalle agronomist Jason McClintock, Ag ‘n’ Vet Services, said entire lupin crops had been devastated.

“The lupins are just not handling the frost; they’ve aborted their flowers on their primary stem spikes and they’re looking very sad. Whether they’re going to recover, I don’t know,” he said.

Mr McClintock said long-term loss was unknown.

“I’ve never seen whole paddocks affected in the past. I’ve seen low lying areas but there is certainly whole paddocks of lupins damaged this year,” he said.

“I can’t say growers have lost them yet. If we get some rain there will be some lateral branches that will continue to flower.”

South-west and north of Weethalle had been drier and suffered the most frosting, but variation in crop development meant the extent was inconsistent, Mr McClintock said.

He hadn’t yet assessed cereal crops, but said they weren’t as advanced as crops further west.

Early flowering canola had also taken a hit, but Mr McClintock was confident they could bounce back.

“Canola could be okay if we get enough moisture and the temperature’s right and it continues flowering,” he said.

“There’s certainly damage, but how much damage will depend on how much rain and how much the season goes with us in the next month.”

Agronomist Chris Baker, Ag ‘n’ Vet Services, Forbes, said mature canola crops west and north of Condobolin had taken a big hit, and the August 3 frost had damaged grain already formed in the pod.

Lupins had also suffered.

“The main stem (in lupins) has a vertical split from the frost injury and the pods that had set are gone,” he said.

“It’ll die from that split point and whether disease gets into it or not is another thing.”

Mr Baker said growers west of Forbes hadn’t sown noticeably earlier, but mild conditions had accelerated crop growth.

Crops around Condobolin were still being assessed, and Trundle would be checked later this week.

Damage was also reported south and west of Wagga Wagga, including around Rankins Springs, Ardlethan, Lockhart and Boree Creek, and as far south as Deniliquin.

As at August 13, the Wagga Wagga district had recorded nine frost events for the month with the lowest temperature hitting -3 degrees Celsius.

The average number of August frosts for Wagga is 11, said Wagga Bureau of Meteorology technical officer Robbie Lennard.

He said Wagga had averaged overnight minimum temperatures this month of 0.2 degrees, which was 3.4 degrees below average.

The total monthly rainfall so far was 1.6 millimetres, which was 49mm below average, and yearly rainfall was 339.4mm, 34mm below average.

For the forecast, on August 16 Wagga has an 80 per cent chance of between 1mm and 4mm of rain and on August 17 a 90pc chance of between 4mm and 10mm.

Griffith has an 80pc chance of between 2mm and 8mm on August 16 and a 70pc chance of 1mm to 6mm on August 17.

Deniliquin has an 80pc chance of between 1mm and 4mm on August 16 and a 70pc chance of 1mm to 5mm the following day.

“Generally... the rain will fall mostly (across) the northern and western Riverina on August 16 in the 1mm to 5mm range, but most of the southern and eastern Riverina is in the zero to 1mm range,” Mr Lennard said.

“For the South West Slopes on August 17, the most likely amount is between 5mm and 10mm.”

The seasonal outlook released late July suggested August, September and October would be generally drier than average and daytime maximums and overnight minimums would be warmer than average, he said.

GOOLGOWI farmer Matt Bunn is waiting to see just how much his wheat’s yield has been affected after 40 per cent of the crop was hit by frost this week.

Of the 2200 hectares of wheat planted at “Mulgowi” about 970ha had been damaged.

A frost event on the morning of August 3 that reportedly dropped to -4 degrees Celsius is to blame, Mr Bunn said.

He said once the heads of the wheat developed he could assess the severity.

“The worst seems to be the ones at the second to third node stage, and that was most of our Gregory wheat sown at the end of April, which isn’t too early as far as sowing date goes,” said Mr Bunn (pictured).

His agronomist Allan Tonacia, Elders Griffith, said the damage would carry a yield penalty.

“If the season had remained to be an average season we were on target for yields of between 2.5 and three tonnes a hectare, but it’s going to reduce that yield to about 2t/ha,”?he said.

Mr Tonacia said if weather conditions were favourable the plant could compensate and regain some of its lost yield.

“You’re not going to get a whole feel for the picture until the crop’s out in head.”