22 November 1996

Maize row space challenge

By Peter Hill

RESEARCHERS and seed houses keeping an open mind on how best to sow forage maize could present a challenge to drill manufacturers and maize contractors if growers end up moving away from the traditional 76cm (30in) row spacing.

Sowing maize in narrower rows but extending seed spacing within the row could lead to increased plant density with more favourable inter-plant spacing.

Trials at the Centre for Dairy Research, which hosted the Maize Growers Association forage maize demonstration, suggest this approach gives earlier ground cover, reducing the need for chemical or mechanical weed control, while increasing light interception for higher yields.

Any spraying would need to be done using row-crop wheels and tyres, however, and harvesting using a conventional "torpedo" header would result in higher losses.

Drill suppliers say adapting their equipment would be relatively easy; meanwhile sales of wider-working drills are growing as contractors gear up to cope more economically with increasing acreages. "The four-row market is dead and six-row drill sales remain strongest," says Mark Unitt of Becker importer Danagri. "But some contractors are taking the plunge with bigger outfits. We have sold two 12-row HKT drills this year, capable of between 600ha and 800ha (1500 and 2000 acres) a season each," Mr Unitt adds.

The HKT unit folds its wings to a vertical position for transport with telescopic outer sections cutting the machines overall height.

Richard Hutchinson of Gaspardo importer, Mill Engineers, confirms buoyant interest in eight-row drills – which makes the availability of Gaspardos eight-row "SP" drill and front fertiliser hopper system particularly timely.

"Going from six- to eight-row drilling increases work rate by at least 25%," he points out. "And provided harvesting is done with a Kemper header, any unevenness in bout matching is no problem."

The revised hydraulic folding mechanism on the "SP" drill folds the wing sections vertically, but the drill units remain upright, so there is no risk of seed loss or need to empty the hoppers completely between fields.

The 500kg (10cwt) front hopper has a pto or hydraulic motor-driven fan plus ground-wheel driven metering unit, with fertiliser blown to a "mushroom" type distribution tower on the drill. Re-filling is straightforward because of the hopper shape and location, and weight distribution is more even than where fertiliser is carried on the drill.

An eight-row "SP" drill with fertiliser placement is priced at about £15,000.

Amazone has introduced an eight-row hydraulic fold drill following an encouraging response to the "ED" model. First-year buyers include the Centre for Dairying Research for the maize events demonstration and variety plots, as well as the centres own commercial crop.

"Accurate fertiliser placement, through a parallel linkage-mounted opener and individual row metering, and the convenience of a wide opening hopper for filling from big bags, have proved attractive features," says an Amazone spokesman.

Accord has improved fertiliser placement facilities on its Optima maize drill by replacing a simple auger screw and holes arrangement with a proper metering unit for every two rows.

The plastic hopper remains on the drill, which is available in sizes up to 12-row. &#42

Larger drills are gaining popularity; this eight-row Gaspardo "SP" from Mill Engineers with 0.5t front fertiliser hopper and pneumatic transfer/ distribution system is priced at about £15,000.