27 July 2001

Workshop sweat turns rolling and spraying into single task

By Wendy OwenNorth-east correspondent

MOUNTING a spray bar on a set of rolls so pre-emergence herbicide can be applied when rolling has cut application costs by £2.25/ha on a farm near York, saving £1800/year.

Farm manager Tony Biggin has used the home-designed unit for two seasons at Warter Priory Farms, mainly on the 800ha (1976 acres) of peas and oilseed rape.

The cost of the combined rolling and spraying operation is £8.50/ha, compared with £7.40/ha for rolling alone and £3.35/ha for conventional spraying, he says. That represents a saving of £2.25/ha, worth £1800/year across 800ha of cropping.

Working at 100 litres/ha each fill covers 20ha, with filling time speeded up by pre-mixing spray in a mixer-bowser. At a forward speed of 7-8.5kph, output is 6ha/hour, with a maximum area treated in one day of 60ha.

"We looked long and hard at fitting a boom to a set of 12m folding rolls, but the overall geometry of the rolls made that impossible," says Mr Biggin. "That meant we had to use 12m rigid rolls instead.

"We redesigned the boom attachments to get the correct jet cover and had to fit a separate pump to transfer chemical from one tank to the other.

Initially, the two 1000 litre tanks were lined in sequence, but that didnt work properly on our steep hillsides."

A Case MX150 is normally used to pull the unit, which is towed from one end using hydraulically operated land wheels for road transport. All motors and pumps are hydraulically powered and the rolls are pulled via a T-link from the hydraulic arms. &#42

ROLLER SPRAYER

&#8226 Pre-em herbicide application.

&#8226 Saves £2.25/ha, £1800/year.

&#8226 Output 6ha/hour.

&#8226 Max area treated 60ha/day.

&#8226 Requires 150hp tractor.