Lower rainfall for Wheatbelt

Below-average winter rainfall is set to continue for the Wheatbelt, although eastern districts could experience more favourable spring conditions.

The latest forecast from the Department of Agriculture and Food's Statistical Seasonal Forecasting system for the three months from June to August indicates there is less than a 30 per cent chance of achieving above-average rainfall.

The forecast is based on May conditions and is backed by a moderate (60 to 75 per cent) predictive skill.

The SSF longer-term June to October outlook indicates below- average rainfall for western parts of the Wheatbelt, but near-average rainfall is forecast for eastern parts favoured by tropical moisture feeds.

Principal research officer David Bowran said the forecast was likely to have an impact on crop yield potential in low rainfall areas, where soil moisture was low and there had been patchy crop emergence.

He said while growers would be cautious about input expenditure, such as nitrogen fertiliser and fungicides, it was worth investing in measures to best capture the benefits of improved spring rainfall.

"Control weeds, insects and mice to maintain water and leaf area for crops so if rainfall improves in August/September, the crop can capture all the benefits, while if rainfall remains low there can be more moisture in the soil to sustain limited grain filling," he said.

Dr Bowran warned that recent warm conditions would accelerate crop growth from five to six days for a leaf to emerge compared with more normal six to eight days.

"We will see flowering for many wheat crops emerging in mid-May by up to two weeks earlier than predicted using Flower Power, so mid to late August flowering of Mace wheat is highly likely again unless we get really cold temperatures in July and August." he said.

Dr Bowran said livestock producers would also have to manage their feed regimes carefully.