19 May 1995

Direct answer to soil blow

One Notts beet grower avoided soil blow, frost and herbicide problems this spring thanks to direct drilling. Dick Palmer visited him to find out more

SEVERAL techniques have been tried to counter the problem of windblown soil which used to occur about eight years in 10 on the light sandy land at G T Wagstaff & Sons Holly House Farm, Scaftworth, on the Yorks/Notts border.

Previous attempts included ploughing and pressing, and even straw planting, but had limited success. "In the past we have had to re-drill up to three times on some areas," says Trevor Wagstaff. "You can replace the seed but not the lost growing season." Up to 75% of the farm is prone to blowing if not protected.

The farms own borehole annually provides 125mm (5in) of water for the beet. This helps achieve yields on a par with the local factory average despite the soil type.

Switching to direct-drilling, now practised for 10 seasons, has been an evolutionary process. Ploughing and pressing before drilling still left the land vulnerable. And "dragging" (cultivating) rather than ploughing the previous years cereal stubble resulted in serious drill blockage.

A Shakeaerator was then tried. But it left deep grooves unsuitable for drilling into. Determined not to be beaten, the Wagstaffs designed their own five-leg cultivator with shallow, flat-lift-type winged sub-soiler tines with a disc in front of each to reduce surface disturbance.

Stubble in situ

Using it results in considerable soil upheaval but minimal inversion, leaving the stubble in situ. Set about 250-300mm (10-12in) deep, the 500mm-spaced tines lift the land about 50mm (2in).

A Cambridge roll is towed behind to re-level the surface without leaving fresh wheelings. Any compaction under the previous years tramlines is taken care of by the close-spaced tines.

"We drag diagonally across the field so the drill does not follow the slits made by the cultivator, and to provide a better ride for the sprayer," explains Mr Wagstaff.

Two to three weeks after working, a Stanhay Webb Selekta 5120 drill, now in its second season, is used to sow the crop directly into the stubble debris. Every effort is made to minimise the trash problem by cutting the previous winter barley shorter than usual and baling carefully.

The Selekta drill has a heavy-duty chassis with double disc furrow openers to cut through surface trash. Each drill unit has a 160mm (6in) wide stainless steel front wheel and a slightly wider zero-pressure tyre behind. The rolling action firms the ground but not enough to cause capping.

Agronomy modified

Agronomy has had to be modified to suit the direct-drilling technique. Cereal volunteers are sprayed off with glyphosate the previous autumn and again in the spring.

Salt, phosphate and potash according to soil indices are applied in the autumn and left to wash in over winter. "Not incorporating the fertiliser doesnt appear to matter," says Mr Wagstaff.

No pre-emergence herbicide is required due to the stale seed-bed approach and because surface organic matter could render residual products ineffective. "Wait and see" weed control tactics are adopted, with contact-acting materials applied as necessary.

This spring the technique has brought an unexpected bonus. With limited weed growth, Mr Wagstaff delayed the early post-emergence spray, so avoiding the late frost/herbicide combination which damaged crops elsewhere.

Apart from any cost-saving, it is still too early to tell if direct drilling offers a yield advantage where blowing is not a problem. But reduced moisture loss and the ability to drill earlier should be an advantage. This year Mr Wagstaffs Saxon, Aztec and Zulu crop, sown on Mar 15-18, had emerged by Apr 14.