A NEW development in controlled traffic has come out of Western Australia. Building on the standard bare tramline farming system, fuzzy tramlines seek to maximise yields and dollar returns by cropping in the tramlines as well as the remaining crop area.
A classic case of serendipity, the concept of fuzzy tramlines emerged from an accidental spraying of seed into tramlines in a 1999 trial of farming with bare tramlines.
Developed into a full-scale, onfarm trial, fuzzy tramlines are formed by spraying seed from a seeder hose towards the ground from a height of about 800 mm in front of a frame or airbox wheel.
The wheel then rolls the seed into the surface soil. The spreader is twice the width of the seeder, and the sprayer is three times the width of the seeder.
Thus, the fuzzy tramlines may have no further traffic during the same season, or one pass of spreading traffic, or two passes - one of spreading and one of spraying traffic. These trials also compared the yield and weediness of each type of fuzzy tram line with bare (unseeded) tramlines.
According to Paul Blackwell of the WA Department of Agriculture, the advantages of fuzzy tramlines are clear from the trial results, despite a difficult season for crop establishment.
"Wheat yield in the fuzzy tramlines was about half of the yield in the rest of the crop in the unwheeled areas," he said. Although half might not sound like much, it is better than the zero yield that would normally come off bare tramlines on the sandy soils in Western Australia. The results are reflected in a higher gross margin for the whole paddock (see graph), with a fuzzy tramline system returning an extra $15 per ha gross margin compared with a cropping system using bare tramlines.
Reduced soil erosion and a 60 per cent suppression of ryegrass in the tramlines provided some additional benefit. This was a good result given that there was no attempt to control weeds in the tramlines.
"If we'd had a better start to the season, it is possible that there would have been more opportunity for more vigorous wheat growth to compete with the ryegrass after wheeling from spraying or seeding," Dr Blackwell said. The trials did identify one minor problem with fuzzy tramline farming - the fuzzy tramlines were more difficult to follow when spraying or spreading than bare tramlines.
"Growers using single fuzzy tramlines this year have found them easy enough to follow in cereals, but more difficult in lupins or canola," Dr Blackwell said. "Single bare tramlines would be easier in lupins or cano1a." He suggests that electronic tramline controllers, currently available from Europe, would help because they can know which tramline is being run by the seeder. If bare tramlines are needed for guidance, then a series of solenoids divert the flow of seed to the rows accordingly.
Automatic steering and full electronic guidance for all tractors theoretically dispense with the need for bare tramlines for visual guidance. However, Dr Blackwell points out that having some form of tramline and electronic automatic steering would be good insurance for occasions when the electronic system may be unavailable.
Electronic guidance can be employed most efficiently when used only on the seeding tractor a single fuzzy or bare tramline laid out at seeding then guides the spraying and spreading operations.
Alternatively, for lower cost, a contractor can use electronic guidance to mark out the path of the seeding tractor with a tine or a drag chain.
Program 4 Contact: Dr Paul Blackwell 0899568537 email PBlackwell@agric.wa.gov.au