VICTORIA'S grain harvest is about 70 per cent complete, with the quality of crops holding up well against heavy rains.

GrainCorp regional manager for southeast Australia Scott Whitmore said the northern Mallee harvest was 95 per cent completed, while farmers in the southern Mallee and Wimmera would soon finish harvesting their wheat and barley.

Mr Whitmore said Western District growers were halfway through the canola harvest and the first wheat and barley was just starting to be delivered.

"The wheat quality has been good (across the state)," Mr Whitmore said.

Harvest is almost complete in the largest grain growing state, Western Australia.

CBH Group has received about 10 million tonnes of grain, with receivals expected to wind up by the end of this week.

A better-than-expected canola crop was produced in Western Australia.

The Australian Oilseeds Federation's December report increases its estimate of the West Australian canola crop by 25,000 tonnes from last month to 850,000 tonnes.

The AOF has cut its forecast for the national canola crop by 25,000 tonnes to 1.77 million tonnes, largely due to a 60,000-tonne drop in the Victorian harvest.

Victoria is now expected to yield 390,000 tonnes - the biggest crop in six years.

Meanwhile, AWB said it would finalise last season's wheat pool next March - one month ahead of schedule.

AWB commodities general manager Mitch Morrison said the move would help growers' cash flow as they prepare to sow next season's crop.