16 August 2002

Time to turn to precision?

By Edward Long

PRECISION drilling cereals is the last piece of the precision farming jigsaw, offering the potential to slash seed costs by over £54/ha (£22/acre) and improve crop management.

By accurately spacing seeds input costs can be cut, and both the genetic potential of the seed and the latest seed treatment technology exploited to boost yield and profit, says Chris Brown of Stanhay Webb, the company that has developed a precision drill for cereals and mainstream combinable crops.

"The time has come for precision drilling cereals. With low grain prices growers are looking for ways to optimise gross margins. This is possible by reducing seed costs, by accurately spacing less seed. With fewer plants there is less disease pressure, so there is scope to trim fungicide use."

"Recently we realised the weak link in the precision farming chain was drilling so have developed our Dart drill. It is the first to be able to drill combinable crops accurately.

"For precision drilling top quality seed with 99% germination, a known level of disease, and the best available seed treatment to match the situation should be used.

"Trials suggest for wheat a target of 80 to 100 seeds/sq m is ideal for most early drilling dates, increasing through the season, so there is scope to at least halve seed costs."

The Dart drill has been developed over six years, and for the past three seasons pre-production prototypes have been trialled on farms in the Border area of Scotland and in Yorkshire.

In the Scottish trial the seed-rate for wheat was slashed from 249kg/ha to 49kg, which at a seed cost of £275/t was a saving of over £54/ha or almost £22/acre.

Evidence from these trials suggests precision-drilled cereals are more even, as there is less inter-plant competition, and, as there is more air movement in the crop, there is a better micro-climate and less disease pressure. Rooting is also better, so there is less chance of lodging.

"Precision drilled crops definitely look better and yield at least as well as conventionally sown crops, even at the greatly reduced seed rate."

Seed-bed conditions affect output, so ideally a traditional plough and cultivations system, rather than min-till, should be used, and power harrowing avoided as it can create sticky conditions.

"Growers who ignore precision drilling will be missing a trick. Gross margins will be improved, so we calculate just 600t of extra grain will cover the cost of the drill. It ought to pay for itself within three years," says Mr Brown. &#42

HOW IT WORKS

The air-drill uses dual disc metering technology to cope with a range of seed sizes. Seed is placed on the individually metered set of discs located just 5cm (2in) above the seed-bed. Each drill unit, early production models are designed for 18 or 24 row working, is staggered on the frame to allow a minimum row width of 16.6cm (6.5in) to be achieved.

Parallel linkage on the chassis provides independent suspension, each unit having 500mm (20in) of travel to cope with uneven contours whilst maintaining accuracy of sowing depth.

Every row has its own dedicated metering unit. Seed is blown down from the front-mounted hopper via cyclones to the metering units just above the seed-bed. Each unit is fitted with a rear wheel for good seed/soil contact, the slight consolidation it provides should deter slug movement in the soil.

The drill can operate at a forward speed of up to 8mph without compromising accuracy. This matches a conventional cereal drill, but, as the Dart is not as wide, between 3m and 4m, output is less.

PRECISION SOLUTIONS

&#8226 First precision drill for a wide range of combinable crops.

&#8226 Scope to halve seed costs.

&#8226 Less risk of disease and lodging.

&#8226 Yields at least as good as from conventionally-sown crops.

HOW IT WORKS

The air-drill uses dual disc metering technology to cope with a range of seed sizes. Seed is placed on the individually metered set of discs located just 5cm (2in) above the seed-bed. Each drill unit, early production models are designed for 18 or 24 row working, is staggered on the frame to allow a minimum row width of 16.6cm (6.5in) to be achieved.

Parallel linkage on the chassis provides independent suspension, each unit having 500mm (20in) of travel to cope with uneven contours whilst maintaining accuracy of sowing depth.

Every row has its own dedicated metering unit. Seed is blown down from the front-mounted hopper via cyclones to the metering units just above the seed-bed. Each unit is fitted with a rear wheel for good seed/soil contact. The slight consolidation it provides should deter slug movement in the soil.

The drill can operate at a forward speed of up to 8mph without compromising accuracy. This matches a conventional cereal drill, but, as the Dart is not as wide, between 3m and 4m, output is less.

PRECISION SOLUTIONS

&#8226 First precision drill for a wide range of combinable crops.

&#8226 Scope to halve seed costs.

&#8226 Less disease and lodging.

&#8226 Yields at least as good as from conventionally-sown crops.