Cracking the code on Wheatbelt soil constraints

Lime incorporation and strategic tillage are hoped to help crack the code on central and eastern Wheatbelt soil constraints.

Application and incorporation of lime with tillage will be hot topics at the Cunderdin Crop Updates hosted by WANTFA on March 3 with Greg Shea from the Department of Agriculture in Merredin presenting the latest results on the topic as well as Ty Henning from Tek Ag Koorda, who will be presenting on the economics of lime incorporation.

Greg Shea and Tony Murfit comparing roots of plants under different treatments in Merredin. PHOTO: Lauren Celenza

Mr Shea said it was very important to design a system that gave an economic return to lime as quickly as possible, especially in low rainfall areas where margins can be slim. Research findings from the GRDC funded Focus Paddock project had shown that 20 per cent of paddocks surveyed through the Wheatbelt had pH profiles unsuitable for Canola.

“Canola is more sensitive to soil acidity than wheat and is worth more per tonne, therefore it would appear to be sensible to try to get the benefits as quickly as possible with the highest value crop to pay for the big cost of getting the lime to the farm,” he said.

Mr Shea has some new data from a large scale trial carried out with Tony Murfit, Manager of Warrakiri Farms Burracoppin, on the effects of deep ripping and liming in low rainfall areas like Merredin.

“Once soil constraints are removed, this country is more reliable for cropping as the water availability to the crop is generally higher,” Mr Shea said.

“Tony is finding out for himself whether the incorporation and mixing of the lime in the fallow year is speeding up the time it takes to ameliorate the toxic subsoil.”

Mr Shea believes that as well as canola having a big part to play in the economic response from lime, the break crop also had additional benefits of disease and weed control.

Mr Henning’s 2014 trial in Koorda looked at the economics of different lime incorporation methods on a low input farm.

He said growers were great at getting topsoil acidity under control, however when it came to the subsoil, many were missing out on potential moisture under the acidic plant root barrier.

Lime rates in the trial varied from 1-10t/ha with varying incorporation methods run across the paddock after application.

“We looked at the cheaper, on farm gear like rotary hoes to the Rolls Royce of ploughing equipment like the mouldboard plough and spader,” Mr Henning said.

“Most growers have been applying 3-5t/ha of lime over the years which has increased the pH of topsoils to about 6, but the subsoil pH is still critically low. We need to increase the subsoils pH to increase the soils bucket size.”

Other key topics of the day include dry seeding, ryegrass control, grain marketing, crown rot and rhizoctonia management, fertiliser use efficiency as well as a comprehensive spray workshop.

For more information please email lauren.celenza@wantfa.com.au.

Program link here

Email: Lauren.celenza@wantfa.com.au
Phone: 0419 908 793