A new precision-placement grain drill coulter capable of improving drilling accuracy and germination rate - and therefore allowing seed rate reductions of up to 15% - has been awarded a gold medal for technological development at the Agritechnica 2003 machinery event in Germany (Nov 9 - 13).
Developed by Kuhn Farm Machinery for use with its established Venta pneumatic seed drills, the Accura precision coulter achieves consistent inter-plant spacing through the combination of gravity feed and a novel seed separation device within the coulter. In addition, consistent seeding depth is achieved through adjustable coulter pressure and a guiding press wheel.
Gravity feed of the seed through the coulter system is made possible by the diversion of air away from the seed placement zone by an air filter at the end of the seed pipe. Without the filter, the air blast normally associated with pneumatic drill seed placement would cause seed to bounce off the bottom of the coulter furrow, thereby reducing accuracy. Gravity feed is complemented by the seed separation device, which comprises of a series of ramps down which the seeds slide and separate on their way into the seedbed. This system is called Cascade and is contained within an easily interchangeable cartridge. Versions are available for small seeds (e.g. rapeseed), cereals and large seeds (e.g. peas, beans).
The Accura system has been tested independently and has shown significant improvements in seed placement accuracy and germination when compared with conventional coulter performance. The scope of improvement is sufficient to allow seed rates to be reduced by 10-15% and still achieve the same plant density. The gold medal received at Agritechnica 2003 was awarded by DLG (Agricultural Society of Germany).
The Accura system can be fitted retrospectively to existing Venta pneumatic drills, with the cost for a 4-metre machine being around £1000.
