17 October 1998

SCORE ON DRILLS

Marked differences emerged when British Sugar carried out its first tests in 10 years on beet drills. David Millar summarises the results.

UNIFORM plant populations and the good, even establishment promised by a first-class drill have become vital now that treated sugar beet seed can be worth around £160/ha.

All but one – Stanhay – of the major drill manufacturers with UK outlets responded to the British Sugar challenge back in the spring to put forward drills for assessment on both a sandy loam and a clay loam at Helpston near Peterborough, Cambridgeshire. The manufacturers used their own operators but they were set performance targets by BS project manager Philip Ecclestone.

British Sugar specialists also assessed each drill – from a mixture of mechanical and pneumatic models – for other factors, including options, hopper capacity, and ease of adjustment, maintenance, transport and mounting. The Sugar Beet Research and Education Committee funded the trials held on one day.

No one machine is picked out by BS as the ideal drill since farms will vary in their requirements, subject to soil type and drilling needs for other crops. However, it is possible to see which of the drills were the most consistent in performance at the standard specification set by BS. Each manufacturer supplied a six-row or 12-row drill, set at 50cm row widths, with the seed spacing as near to 17-17.5cm as possible.

Each machine was assessed over 12 rows at two different speeds – 4kph and 6.5kph. Ideally, the results should show the highest peak of plants emerged around the 17cm mark. Mr Ecclestone suggests any lower second peak should be at 34cm to account for those seeds which fail to germinate or come through, or where placement was missed. Ideally, all seeds should, of course, germinate.

In practice, drills on the lighter soil were more likely to produce a narrower seed spacing than the same drill might produce on the heavier loam. Plant spacings also became more varied at the faster of the two speeds.

Mechanical drills appeared to be the most effective at getting accurate spacings, while the pneumatic drills – designed for use with other types of seed – were slightly less consistent. The Kleine Synchro and the Accord Monopill S – both mechanical – stood out for their ability to place seed as close as possible to the 17cm target.

"When you look at plant populations, however, some of the pneumatics havent done too badly on that," points out Mr Ecclestone. "We recognise with the pneumatics that the trade-off is a drop in accuracy. Most growers will realise this when they choose those drills for other reasons."

&#8226 The full results and some of the drills will be on show at next weeks Beet UK demonstration at Aubourn Farmings Nevile Estate, Wellingore, Lincoln, on Wed 21 Oct.

Drills put to the test

Drill Type Supplier

Accord Monopill S Mechanical Ferrag (01942-272777)

Accord Optima Pneumatic Becker Centra 2000 Mechanical Kongskilde UK (01263-713291)Gaspardo SP 530 Pneumatic Mill Engineers (01285-740408)

Herriau Turbosem Pneumatic Standen Reflex (01353-666200)

Kleine Unicorn Synchro Mechanical Garford Farm Machinery (01778-342642)

Monosem Mecca 2000 Mechanical Armer Machinery

(01485-520318)

Nodet Planter Junior Pneumatic Kuhn Farm Machinery (01952-239300)