5 September 1997

US drill scores in simplicity

By Andy Collings

GREAT Plains – an evocative designation for a North American built drill and one which conjures up visions of vast wheat fields, hot summers and no little dust.

But it is in the UK where fields are smaller, summers less predictable and dust can quickly turn to mud, that the Great Plains drill is now looking to prove its worth.

Imported by Bob Wallis, based at Upper Dean, Beds, the drill is available as a one-pass unit for sowing directly into stubbles and as a conventional build for traditional plough and cultivate systems.

Working widths are 12ft, 15ft and 20ft – the use of imperial measurements reflects their Stateside construction. Potential purchasers might also like to consider how such widths will work in with existing spraying and fertiliser spreading equipment.

The one-pass version employs a set of discs attached to the drills drawbar. Capable of being operated independently of the drill unit, depth control is such that, in hard conditions, weight can be transferred from the tractor and/or drill to increase penetration.

Coulters comprise two opener discs to create a seed slot followed by a press wheel – the latter also responsible for depth control.

Coulter penetration can be adjusted by altering the pressure of individual springs. With seed metered from a 850kg capacity hopper (12ft version) by a set of fluted rollers driven from a four-speed gear box, the package adds up to a pretty conventional system.

But that is where the Great Plains drill may score.

Undoubtedly strong – the drawbar/disc assembly on the 12ft version has the same box section dimensions as the 20ft – it offers a relatively uncluttered system which, it is claimed, has found favour in a wide number of other countries.

How does it perform? To be fair it was not a good day at Keysoe, Beds, where heavy overnight rain created ground conditions which would have normally confined most drills to a week in the barn.

Inspection of the previous days drilling however, revealed well placed and adequately-covered oilseed rape seed with Mr Wallis maintaining that, with a 150hp tractor, the 12ft, one-pass unit had been working at speeds in excess of 10mph. But then, most drills worth their salt would have.

The interesting question which needs answering – for all drills – is where are their limits when soil conditions take a turn for the worse? In a catchy autumn such information would be useful, to say the least.

For the Great Plains drill, a simple disc cultivator combined with a conventional coulter system, could conceivably see it attracting some attention.n

Great Plains in action. Note the front disc/drawbar assembly.

GREAT PLAINS DRILL

&#8226 Working widths: 12ft, 15ft, 20ft.

&#8226 Version: trailed, mounted, cultivator/drill.

&#8226 Coulter spacing: 6in.

&#8226 Hopper capacity (12ft): 850kg.

&#8226 Sample price: 12ft cultivator/drill – £27,700.

Coulter detail. Wheels and springs are adjustable for depth control.