News > Day Two > Keep field traffic to a minimum
Developing a zero till cropping system, where the only vehicle or machinery traffic on the field is strictly limited to tramlines, will dramatically improve overall soil health and crop yields, says an Australian farmer speaking to western Canadian producers in Edmonton this week.

Australian producer Robert Ruwoldt (l) speaks with a Canadian farmer following his address at Farm Tech in Edmonton. -- Lee Hart photo

Robert Ruwoldt, who along with his family crops about 7,000 acres of grains, oilseeds and pulses in southeast Australia, told farmers attending the 2010 Farm Tech conference in Edmonton that his controlled traffic farming (CTF) system nearly doubles the yields and returns on his fields, where he has practiced this approach for several years.

"It all comes down to minimizing compaction and improving the ability of the soil to store moisture," says Ruwoldt, whose farm receives about 15 inches of precipitation per year.

The tramlines are the only place where any type of vehicle traffic is allowed to run. He uses the same tramlines for seeding, spraying and harvesting. And if someone comes to the field in a pickup and wants to talk to him, he or she must walk to where he is.

Whether in Australia or Western Canada, farmers do not appreciate the impacts that vehicle and machinery traffic have in causing soil compaction, Ruwoldt says.

On average, with the usual traffic over a field to seed, spray, combine and remove grain at harvest, as much as 40 per cent of the field will have been driven on, whereas with his tramline system that figure is reduced to 11 per cent.

Referring to an example with lentils, he says crop yields were reduced by 55 per cent when seeded in areas which had been driven over at least once, compared to areas where they had been no machinery traffic.

In another example, he said the actual returns from crops grown on land with no machinery traffic was double that of where there had been machinery traffic -- $603 per hectare, versus $289 per hectare.

In his view, soil compaction is one of the "biggest issues facing agriculture in the world." Anywhere machinery or vehicles travel in a field, even once, causes some compaction, which can increase weed seed germination and affect moisture's overall infiltration of the soil.

Ruwoldt showed slides during his presentation of a neighbouring field on which, after a rainfall, areas were flooded, whereas on his land all water had infiltrated into the soil.

Limiting vehicle traffic on the field, and using the same tramlines for every operation, eliminates soil compaction over most of the field, improves the tilth of soil, stimulates the activity of microbes and earthworms in the soil, and allows crop roots to develop more fully so they can access moisture and nutrients, he says.

-- Lee Hart is a field editor for Grainews in Calgary.