Mapping helps spot non-wetting soil profiles

Australian grain grower of the year Trevor Syme says there is no magic pill that will solve the challenge of WA's non-wetting soils.

But the Bolgart farmer believes that with a long-term view and a commitment to invest in different solutions to suit different soil types, farmers with non-wetting soils will see tangible results and will benefit through increased yields.

Presenting his findings to the WANTFA Crop Updates in Dowerin, Mr Syme said 80 per cent of his soils on his central Wheatbelt property were non-wetting, but after many years of trialling different techniques, no single solution could be used across his entre farm.

Mr Syme has compared claying, delving, spading and mouldboard ploughing to find the cheapest technique that delivers the most profitable outcome.

"Full soil disturbance and cultivation does go against the grain in regard to no till, but it's a compromise. For one year of full cultivation you will hopefully get a lifetime gain," he said.

And despite the recent interest from farmers across the Wheatbelt in mouldboard ploughing, Mr Syme believes it has limited value on soils without clay.

"Where you can reach the clay it does a good job, but on the sand, if you aren't bringing any clay up, I think you are wasting your money," he said.

"All you are doing is burying the weeds, but you are not alleviating the non-wetting.

"White sand is white sand no matter which way you turn it."

A combination of claying, delving and spading has delivered the most cost-effective results to Mr Syme's property.

But he admits it has been an expensive exercise.

"The most expensive method, which is a combination of claying, delving and spading, is the clear winner in terms of long-term profit improvement, but that can cost as much as $1000 per hectare," he said.

Mr Syme conducted a trial to establish if there was a return on the investment in non-wetting techniques.

Since that trial, Mr Syme has also used Dual Electromagnetic (EM)and Gamma-radiometric (GR) surveying of his property, which shows the different depths of clay under the surface.

He said this mapping technique has changed his non-wetting tactics.

"Where the map shows up as red, I've spread clay, and where its yellow and green, I have just delved without needing to spread any clay," Mr Syme said.