Be kind to your soil

Tractor on field

Less wheels equals more yields — part II

"Good land management is really about making the most of what you've got," says Queensland soil scientist Don Yule. "We're looking to develop systems that work across the board, are efficient and can be applied across cropping districts."

Dr Yule and agronomist Bruce Radforth of the Department of Primary Industries, Rockhampton, have important news for dryland producers about the benefits of controlling farm traffic. Their studies are showing that growers can increase crop yields and farm efficiency and at the same time cut fuel costs by up to 50 per cent when there's less traffic on the soil.

These are some initial results from a five-year, multimillion dollar project funded by growers through the GRDC and by the Federal Government through the Land and Water Resources Research and Development Corporation.

The project is aimed at ways to control soil compaction and reverse the damage done by compaction in subtropical cropping lands. However, the researchers say many of the results should be nationally applicable across dryland cropping areas.

Farm machinery compacts soils

In the usual approach to cropping, the wheels of farm machinery compress and compact dryland soils. The result: water doesn't penetrate and run off and erosion increase. Seedlings don't establish as well as they could and root and crop growth are stunted.

Dr Yule said that typically wheels cover 15-20 per cent of the paddock in each operation. The tractor loses efficiency in tilling hardened soils and fuel costs rise.

On-farm studies will see how soil compaction and soil erosion are reduced by confining all farm machinery to permanent wheel tracks. The wheel tracks disperse run off and crops are grown only in non-compacted soil between wheel tracks.

Three stage project

This cropping project, which also involves expertise from the CSIRO and Queensland universities, will take results directly to the farmer in three stages — research, management and extension.

Experiments underway now; at the Biloela Research Station and next year at Emerald Research Station are looking at: management options on different soil types; the effects of soil compaction on soil properties; methods to increase crop growth and to repair the effects of compaction such as mechanical tillage, deep ripping, pastures, zero till systems and biological repair.

A smaller experiment at Brigalow Research Station, outside Theodore, will look at the trampling effects of cattle grazing crop residues.

On-farm studies will compare these methods with conventional systems. The extension work will then bring the results directly to growers.

CONTACT: Dr Don Yule 079 360 211;

Mr Bruce Radforth 079 921 044

Region North, South, West