Tillerstar more than a match for conventional potato bed preparation

At work: A two-bed version of the George Moate Tillerstar one-pass tilling, bed forming and stone separating machine.
At work: A two-bed version of the George Moate Tillerstar one-pass tilling, bed forming and stone separating machine.

Growers at the Cereals Event will get to see the unique Tillerstar one-pass implement for potato bed preparation in action in the live working area for the first time.

The practical demonstrations will highlight the positive results of an independent trial in Scotland showing that the Tillerstar is more than a match for conventional preparation systems in terms of yield and quality of the resulting crop.

“Any concerns that one-pass potato bed preparation might produce inferior conditions for crop establishment and yield have been confounded by the results of this trial,” says Lesley Pratt, commercial director at George Moate Ltd. “According to the trial report, the Tillerstar-prepared plots produced one of the highest total and marketable yields and there was no significant difference in quality parameters between the Tillerstar and best cultivation treatments.”

She adds: “The only real difference is that the Tillerstar achieved these results with just one pass instead of three, making significant savings in time, labour and fuel.”

Four flexible finger rollers positioned behind the tiller separate stone and deposit it beneath the bed.
Four flexible finger rollers positioned behind the tiller separate stone and deposit it beneath the bed.

A report on the SRUC trial comparing different cultivation techniques states that if the Tillerstar had been used commercially in the trials field, the resulting crop would have been as good as from any other bed tilling and stone/clod separation system in a difficult year when conditions were not optimal for bed preparation.

“The trial confirms the experience of first operators of the Tillerstar that its unique approach to forming separated beds can be used without risk to any aspect of crop performance,” says Lesley Pratt. “The key feature is that it offers big savings: one Lancashire grower reckons to have slashed £245/ha from his establishment costs.”

The Tillerstar prepares beds using an upward-cutting bladed rotor to cultivate the soil and throw it backwards on to a set of four flexible finger star rollers. Stones and clods are conveyed forwards, dropped across the full width of the bed and then covered by ‘clean’ soil as the machine continues working.

“We were interested to see whether the presence of this material beneath the bed would affect drainage and root development,” says Matt Smallwood, Senior Potato Consultant at the SRUC’s SAC Consulting arm. “The Tillerstar plots did tend to be wetter and possibly didn’t drain as well, and there was some evidence of slight canopy delay; but none of this was detrimental to yield or crop quality.”

In fact, the Tillerstar plots produced one of the highest total and marketable yields in the trial, and the biggest number of tubers larger than 60mm.

“This was significantly more than from the coarser star and web separation treatments and may have significant benefits for ware crop marketing,” notes Mr Smallwood.

All plots showed evidence of a pan caused by the smearing action of tiller blades in the wet soils but the Tillerstar’s rotor, with its upward cutting action contrasting the downward cutting action of conventional tillers, was no better or worse in this respect.

“Nor was there any significant difference in plant rooting depth, which was impeded by the pan to the same extent as other treatments,” says Mr Smallwood. “The same applies when we looked at greening and powdery scab levels.

“There were significantly more growth cracks than in the star separation treatments, which probably related to the length of time the ridges remained water-logged,” he adds. “But cracking was present in most commercial crops last season.”

The trial, sponsored by the SAC Association of Potato Producers and Agrii, explored the possible impact of cultivations on potato crops: “We’re looking into a number of aspects, but in particular crop emergence, canopy development, compaction and rooting depth, incidence of powdery scab and yield,” explains Matt Smallwood.

After ploughing in the autumn, plots for the conventional approach used by most growers were deep ridged, worked down by a bed tiller operating at two different speeds, and prepared by star- and web-type separators, each producing ‘fine’ and ‘coarse’ finishes. This three-pass post-ploughing approach contrasts with the single pass of the Tillerstar, which worked on the ploughing without prior deep ridging.

“Further savings can be made by operating the Tillerstar directly into stubbles,” points out Lesley Pratt. “And its novel feature of depositing stone across the width of the bed rather than in a furrow between beds means the material is readily distributed through the soil profile by subsequent cultivations.”

Further evaluation of the machine will emerge from trials planned with Potato Council funding by Cambridge University Farms at Edward G Harrison in Norfolk.

“This work, investigating how growers can achieve similar or better seed-beds more quickly and cheaply with less de-structuring of soil, puts the Tillerstar right in the centre of the topical debate on the impact of current farming practices on soil structure,” says Lesley Pratt.

The Tillerstar range comprises single-, double- and triple-bed cultivator-separators, each with a choice of 1.82m (72in) and 2m (78in) bed widths. Output is typically 10 acres per bed per day. Adjustable full width forming hoods are available for potatoes, onion sets, carrots, leeks, beetroot and similar crops.