Spraying off cereal crops with a pre-harvest herbicide to produce an evenly ripened crop is a useful means of improving combine output and reducing drier costs, says East Yorkshire grower, Robert Garbutt.
"It's not an expensive treatment, it can save money by making the crop easier to harvest and you get some weed control into the bargain," he says. "Combine performance can be increased by up to 50% in a crop that's evenly ripe and I'd rather take out 1-2% moisture in the field than do it the expensive way using the drier."
Crop clearance beneath the sprayer is potentially a limiting factor for growers who, like Robert Garbutt, would rather do the work themselves than employ a contractor but cannot justify the expense of a self-propelled sprayer. At Mr Garbutt's Manor Farm, Grindale near Bridlington, a novel high clearance tractor handles all crop protection work.
The Landini High Clearance is a factory-built model, not a conversion, he emphasises, with a specially developed transmission and axles. It has four-wheel drive and the same size wheels and tyres all round.
Supplied by East Yorkshire Landini dealer, Steve Gowan, the tractor is used with a 2800-litre trailed sprayer and for fertiliser application handles a three-point linkage-mounted broadcaster.
On its 270/95R48 row-crop tyres, the tractor clears 760mm (30in) beneath the front axle – 700mm (27½in) under the diff – and with the drawbar assembly removed there is little else to disturb the crop.
"It just brushes the top of the wheat, so there's no damage at all," points out Robert Garbutt. "I've used it to spray oilseed rape against sclerotinia and I can go through the barley and wheat with a pre-harvest glyphosate spray without any fear of knocking heads off."
Surprisingly, he says the tractor is as manoeuvrable as the standard model despite being fitted with those big diameter front wheels. That is because it has a 200mm (8in) shorter wheelbase, which results in a tighter turning circle.
"I thought it would be hopeless but it's really very good," says Mr Garbutt. "It'll turn tighter than the tracking drawbar on the sprayer will allow, so there's no point being able to turn any tighter."
In addition to the 270/95R48 tyres used to slip down the tramlines in mature crops, the tractor has a set of slightly wider and smaller diameter 16.9R34 tyres for autumn and early spring work, such as harrowing, rolling, pressing and other light duties.
"We get a lot more work out of the tractor than a self-propelled sprayer but still have its advantages," Mr Garbutt points out.
Landini makes high clearance versions of its 82hp, 92hp and 99hp Powerfarm models, which in addition to crop protection and harvesting operations in cereals and oilseeds are used for specialist work in top fruit, field vegetable, salad and potato production to minimise the risk of impact damage and crop contamination.