Trials fine-tune deep-ripping economics
GroundCover™ Issue: 124 | Author: Brad Collis
Adjacent to the typical farm track leading to Piet Diepeveen’s house and sheds is a trial site that has been driving a paradigm shift in sandplain cropping in Western Australia’s far northern wheatbelt.
This is where a lot of new knowledge on deep-ripping has been coming from in recent years, with the practice now almost universal across this part of the wheatbelt.
With much of the ‘grunt research’ now done, this year’s GRDC-supported Department of Food and Agriculture, WA (DAFWA), trials are more about fine-tuning the economics. The work is being overseen by Wayne Parker, now stepping into the shoes of retiring researcher Paul Blackwell whose research into compaction and controlled-traffic farming has led deep-ripping’s evolution.
The work on Piet Diepeveen’s East Binnu property this year is a tyne-spacing trial; extending the row spacing from 50 centimetres to 100cm to see if this will allow faster operating speeds without losing the yield response that deep-ripping has delivered.
Wayne says the trial is to start a discussion about total area ripped: “Are we able to obtain a greater area ripped at 100cm, therefore a yield response over more area and so more total farm yield, than a smaller area ripped with full hardpan break-out at 50cm?”
This year’s trials have shown that the wider tyne spacing leaves, as expected, an unbroken ridge between the wider-spaced furrows, so researchers will next test if wider tyne points will create more lateral disturbance.
The ripping for this year’s trials was done in February, so the yield effect of the wider row width will not be known until the crop is advanced. However, the primary objective is unchanged: to give roots a passage through the hardpan that exists 30 to 40cm down in the sandplain country.
“Deep-ripping has gathered momentum as rainfall has become more variable and access to moisture more critical,” Wayne says. “Growers understand what it means to have a good deep bucket, and if anything shallows the bucket, like a pH barrier, a compaction layer, or both, it has to be negated. Deep-ripping is one method that will do this.”
There are, however, risks, such as deep-ripping into a sodic layer, which can lead to other soil problems: “You need to know what you are getting your roots into otherwise a lot of money could be wasted,” Wayne says.
Wayne grew up on a farm in the region before joining DAFWA as an agronomist in 2002. He has witnessed considerable change over the years and marvels at the speed of adoption of new technologies and practices: “People are very open to change when they can see where the money is, or where it is being lost.”
GRDC Project Code DAW00243, MIG00016-A