23 August 1996

Windrowing potatoes proves a winner

FOUR seasons ago, Herefordshire potato growers Peter and Simon Vaughan built a windrower from a converted Grimme Continental potato harvester.

Farming out of Kingsland at St Marys Farm, their machine proved so successful that Grimme themselves took elements of the design to produce a factory-built version.

One of these replaced the Vaughans own machine last year, and Peter now says he would never go back to lifting potatoes in any other way.

Windrowing offers three main advantages over conventional potato harvesting, he explains. Firstly, a field can be opened up without the need for a trailer running alongside, with short runs and butts being easier to work.

Secondly, output increases with two machines lifting but only one needing servicing with trailers. Finally, in-field traffic is cut in half, considerably reducing damage.

It is quality, however, which is the key reason why Mr Vaughan has developed the windrowing system. Both his harvester and windrower tractors run on narrow wheels, the aim being to keep all wheelings as far as possible from the crop rows.

Having trailers running in the crop is totally unacceptable, he feels, and with windrowing this is now eliminated.

When opening up the middle of a field, four rows are windrowed into two so six rows are lifted in a single pass. This leaves a gap of just over 5m (17ft) down the middle of the field, and eliminates all trailer damage.

This season, the Grimme Windrower, which in simple terms can be seen as a harvester without a loading elevator, is joined with a new Grimme harvester, the machines having 1.5m and 1.7m (5ft and 5ft 6in) wide webs respectively.

The harvester needs the larger webs to cope with the greater volume of crop and, unlike the windrower, lifts with the haulms intact.

The windrower runs just ahead of the harvester. Windrowing too far in advance is now avoided. Hand picking a windrowed run of 400 yards when it turned wet and loosing a run to frost, is enough to convince Mr Vaughan it is not worth getting too far ahead.

The forward speed of the harvest is now just over 2mph rather than 3mph when lifting without a windrow of crop as well. In practice this slight drop in speed is more than made up for by having a steady supply of trailers, five ferrying the crop back to store.

Mr Vaughan says the harvester is rarely kept waiting, and the bottleneck of having trailers stacked up in the field or store has also been eliminated.

Overall output is up from running two harvesters side by side. It now takes about eight minutes to load a trailer with 10 tonnes of crop.

The Vaughan outfit averages 300t a day.n

The Vaughans Grimme windrower reduces damage and increases output.