IN 1997 Binnu farmer Craig Simkin took a punt with his 3200 hectare continuous cropping program.
He decided to lift and “chock” every second tine of his Ausplow DBS precision seeder, with tine spacings on 25 centimetres (10 inches).
The result gave him the ability to establish lupins on 50cm (20in) spacings without disturbing stubbles from the previous year’s crop.
Mr Simkin followed the same procedure to establish canola in early 2000s, also with the same rationale of handling stubbles.
And it has become standard management practice ever since, while cereal establishment remains on 25cm spacings.
But perhaps what might be called an unintended consequence is that Mr Simkin has also benefitted from a drought-proofing effect, operating in a typical 250mm (10in) annual rainfall zone in the northern Wheatbelt.
“The wider spacings mean plants have more space to access moisture on either side of the road,” Mr Simkin said.
“It’s a typical edge effect.”
Theoretically, with wider row spacings, you also can achieve better weed management from less soil disturbance and more effective inter-row spraying, as the chemical is not caught on plant foliage as much as on narrow rows, where there is more shading.
And with less competition, there should theoretically be more moisture for the crop plants.
Anecdotal evidence from Mr Simkin, and several members of the Northern Agri Group, have shown the ‘theories’ to be true.
One member has gone wider than Mr Simkin and is establishing canola on 60cm (24in) spacings.
But the elephant in the room is wild radish and there always has to be a strategy is to maintain a lot of pressure on weed seed banks.
According to Mr Simkin, through the roller coaster seasons since he started sowing on wider rows, he hasn’t suffered a yield deficit.
“What we’re finding in moisture-limited years is that plants are less inclined to be under major stress,” he said.
“But at the end of the day, you need to manage what you’re doing according to soil type and moisture.”
For Mr Simkin, the almost strict management practice for moisture conservation, involves summer spraying and the normal ‘pre-ems’ and ‘post-ems’.
But inevitably no matter how much attention you pay to moisture conservation, dry spells can throw a proverbial spanner in the works.
Normally Mr Simkin will start his program in April if he gets a wet start.
If that doesn’t occur, he starts dry sowing after Anzac Day, but also inevitably, in April in the northern Wheatbelt, farmers can encounter wet-dry scenarios at the start of seeding, leading to staggered germinations.
That is not a worry for Mr Simkin because with the DBS, he can dig into subsoil moisture which percolates into the seed bed.
“Generally when you get good summer rain like last year, you know moisture is down there and it’s only a matter of accessing it,” he said.
“That’s where I find the DBS is really good at bringing up moisture so I’m not worried by the wet-dry scenario.”
Mr Simkin has also used a bit of home science this year to harvest his lupins, which given the moisture-deprived growing season, meant dropping the header front to pick up pods.
He attached strips of plastic on each alternate bar of the pick-up reel creating a “fan effect” to flick the lupins onto the front (a Case IH 3152 draper).
“The plastic strips created a half bat, half pick-up reel and we didn’t get any pod losses,” he said.
Another home-made bit of gear is a drop chute at the rear of the header to capture trash, which falls onto the tramlines and later burnt – another strategy to reduce weed seed burdens.
