Trials add weight to controlled traffic

More than 150 farmers and agribusiness representatives attended the WA No-Tillage Farmers Association (WANTFA) non-wetting soils and controlled traffic field day at Bolgart last week.

Improving soils have become a hot topic among growers, with non-wetting and compaction issues becoming more common in WA.

"As machinery gets bigger we need to look at ways of reducing compaction and controlled traffic is showing great results and improving production significantly," WANTFA chairman Wes Baker said.

DAFWA soil scientist Paul Blackwell spoke about how and why non-wetting occurred and the effects of different control methods such as soil wetters.

"Non-wetting is mainly caused by waxes on the surface of sand grains and in large particles of organic matter. Material left behind from crops on the surface and in the soil contributes to water repellence, which can build up," he said.

Projects focusing on non-wetting included a spading and clay incorporation trial at Trevor Syme's Bolgart property, Murdoch University research looking into nutritional requirements after claying and DAFWA and CSBP trial results.

"The spading and mouldboard ploughing has shown promise. Spading to incorporate clay was certainly the most effective and it improved the non-wetting," Mr Syne said.

"Mouldboarding has its place but it's got to be done right. If you are just ploughing up white sand there is no point and in some cases you can turn up acidic soil which can be detrimental to the seed bed."

Mr Syne warned spading and mouldboarding could stimulate weed growth, which needed to be considered.

"You can also bring up old weed seeds and make weed burdens worse. I've never seen so many wild oats and I'm still controlling them four years after spading," he said.

WANTFA executive director David Minkey said weed seeds could last under the soil surface for several years.

"Most weed seeds can stay viable in the ground for five to seven years and radish can last around 10, so ploughing should be avoided more than once in a 10-year period," he said.

Controlled traffic was high on the agenda with three WA farmers sharing their experiences with the system, with a common theme being it does not have to be expensive or difficult to get good results.