EARLY rains are expected to create a yield buffer for grain growers ahead of a drier season later on.
The Australian Export Grains Innovation Centre (AEGIC) has made a first estimate of 2014 wheat yields based on the impact of soil moisture and seasonal indicators using its stress index (STIN) model.
Agro-meteorologist David Stephens predicted results on par with the 2013 season.
"Based on the soil moisture in the ground as of June 2 and assuming average rainfall for the rest of the growing season, the average Australian wheat yield should be 2.01 tonnes per hectare, similar to last year," he said.
"However, AEGIC estimates there is a 50-60 per cent chance of an El Nino developing this year which increases the chance of below average rainfall in the southern growing season."
Fortunately, excellent rains across southern Australia during autumn has provided a buffer in many regions against an expected dry finish.
"The good early rains have allowed for early sowing in many regions which is beneficial to crop water-use efficiencies as the average evaporation rates experienced by the crop are less than later sown crops," Dr Stephens said.
When the crop model was run with rainfall to date and rainfall from seasonal outlooks, three distinct regions appeared with a good prediction for the SE region of Australia.
"Early sowing, excellent soil moisture reserves and a less consistent dry El Nino impact means yield potentials are above median for much of south-eastern Australia.," Dr Stephens said.
Overall Dr Stephens said farmers would need to closely monitor soil moisture reserves and seasonal outlooks as winter seeding winds up and nitrogen application rates are considered.
He said a cautious approach was recommended if a high pressure system strengthens over Australia, an El Nino pattern continued to develop and sea surface temperatures cooled to the north of Australia.
AEGIC first warned of the possibility of an El Nino event in early October last year when very low pressure over SE Australia led to a negative El Nino Prediction Index.