ONE OF the canola industry's longest running debates is taking centre stage again this harvest as farmers are confronted with wet paddocks.
Should they windrow their crops beforehand or direct head?
The short answer from technical experts is that there is no one correct answer.
Kelly Angel, Birchip Cropping Group senior research and extension advisor said with the season currently in the optimum planting window in her region in the Victorian Mallee right now paddock access was the major issue.
"The first point to consider is whether you can get paddock access for the windrower to do its job," Ms Angel said.
"If it can't then you might have your decision made for you, but where it can there are various pros and cons to consider," she said.
She said BCG had put out a technical bulletin highlighting some of the different advantages and disadvantages of each option.
"Windrowing generally allows canola to be harvested more quickly because harvesters can travel faster picking up windrows than they do when direct heading in big crops, and secondly, windrowing avoids small areas of late-maturating crop delaying harvest."
However, she said timing of windrowing was everything.
"Recent guidelines suggest the optimum time is when 60 to 80 per cent of seed from the middle third of the main stem and branches has changed colour from green to red, brown or black.
"Grain Orana Alliance (GOA) in NSW has researched timing and the tradeoffs of windrowing and direct heading and has found that often direct heading matches the yields of well-timed windrowing while being better than an ill-timed wind rowing.
"The risk from leaving crops to stand for harvest is driven more by detrimental weather events occurring after the crop is mature."
Ms Angel said BCG was emphasising that if farmers missed the windrowing window then all was not lost pivoting to direct heading.
"Growers need to assess their attitude to risk and ability to undertake a well-timed windrow operation, where access issues weigh heavily, have confidence that not all is lost, it just may mean a bit more focus on harvest timing of sensitive crops is required," she said.
The Grains Research and Development Corporation (GRDC) has also provided information for growers via an online webinar.
Maurie Street, of GOA, spoke at the forum and said being realistic about the ability to get on paddocks prior to that 80 per cent colour change was critical.
"That just won't happen for some," Mr Street said.
But there is more consider even if farmers can physically windrow.
"If you windrow and it stays fine after, then happy days, but if it doesn't you need to consider the risk to the grain sitting in windrows," he said.
"Standing crop will dry quicker and have less yield loss in these conditions."
"It's like having a basket of wet clothes, you can leave them in a basket or put them on a line, the line will obviously dry quicker."