WHILE farmers in the Mid North are all too familiar with frost in spring, the run of freezing nights in early August has left many unsure what to do with their damaged crops.
The extraordinary start to the frost season prompted the GRDC to host a management workshop at Clare last Friday and, in an indication of the widespread nature of the damage, it attracted more than 100 people.
GRDC southern panel member Bill Long, Ardrossan, said farmers were considering cutting their crops for hay or running livestock, depending on what would maximise their returns.
"We're use to dealing with frost at head emergence, but we now realise the impact it can have at the vegetative stages," Mr Long said.
"In April, we planted varieties suited to planting in May - we roll the dice and take risks and this is how it sometimes works out."
Agrilink Agricultural Consulting's Mick Faulkner agreed that early seeding left many plants vulnerable earlier in the season, but he said farmers should not let the risk of frost put them off sowing early.
"We're pushing our farming systems to be early maturing to maximise our yields, but by doing so we actually increase our risk of frost," he said.
"These things are fairly random. It's not that we can plant and get a flowering outside the frost window - it's not as simple as that.
"Don't plant late just to miss out on frost - you're going to miss so many money-making opportunities."
With so many frosts in August - Mr Faulkner reported 21 at Penwortham in the first 27 days of last month - crops at all growing stages were damaged.
Farmers attending the workshop were keen to discover factors increasing or decreasing frost risk in a cereal or pulse crop, such as canopy thickness.
"A high, thick canopy can trap cold air on top of the crop, which can be bad if there are heads poking out on top," Mr Faulkner said.
"However, in a lower, thinner canopy, cold air can go right down to the base of the plant and kill it off at GS31."
Several speakers reported that crops grown with thick layers of stubble on the ground were more likely to be badly affected.
"Stubble does not have any bulk density, it can't hold water and it reflects the light," Mr Faulkner said.
"Unfortunately, stubble is a bad thing for frost."
YP Ag's Chris Davey echoed this finding, but cautioned against destroying the remnants of last year's crop.
"Burning stubble would be too reactive," he said. "Stubble is too valuable for moisture retention to destroy."
Kerin Landmark Rural senior agronomist Steve Richmond outlined how pulses were affected by frosts, and advised farmers to keep an eye out for disease after a frost event. Peas were particularly susceptible to bacterial blight after being hit, while chocolate spot could spread rapidly in frosted beans.
He urged farmers to be prepared to deal with frosted grain before harvest started.
"If you think you're going to have frost-damaged grain, be prepared to store it on-farm at harvest," Mr Richmond said.
"Have silos and bags ready to go."
He said markets would open up in the months after harvest as supplies decreased.
"Your ability to sell your grain will depend on the damage," Mr Richmond said. "It's colour, it's seed size, it's staining and the ability to clean small and shrivelled seed out of the sample.
"There may be some value-adding you have to do on-farm to get that product up to a spec that's saleable."
He said selling opportunities could exist at feedlots while some commercial mills may be willing to buy frosted grain, depending on its appearance.
With frost hitting many areas of SA and Vic, the GRDC is planning a series of frost workshops in affected areas, starting at Kimba tomorrow.
* Full report in Stock Journal, September 4, 2014 issue.