Keeping pastures productive at least cost has seen widespread use of slitters for aeration and drainage, and flexible tine harrows for over-seeding.

But dairy farmer Robin Heath says the kit he bought last spring will do both jobs in one go.

The Prairial harrow combines flexible scarifying tines with levelling blades and vertical slitting knives attached to pigtail tines to renovate pasture. Attaching a small pneumatic broadcaster has added an overseeding capability.

“It’s so handy; I’ve used it to level and re-seed ground churned up around gateways and troughs and to seed bare patches after clearing stacks of silage bales,” says Mr Heath, who farms 93ha at Rushton Spencer near Macclesfield, Cheshire. “All our ground will be harrowed in early spring to give the grass a bit of a lift, applying seed wherever it’s needed.”

Swedish genetics

Efficient grass production is essential for the simple, low-cost approach to grazing and forage conservation used at Lee Farm to maintain a dairy enterprise that is being restructured.

The 150 Ayrshire cows were blended with Swedish and Danish Red genetics to producean average of 6,000 litres. The plan is to rebuild the herd from youngstock and bought-in replacements that will be milked through a robot system.

“I’m looking at all ways of minimising our costs – and in the case of the milking robot, improving my lifestyle,” says Mr Heath. “I love milking cows; I think I’ve only missed maybe three or four milkings since I started at the age of 15. But the strain is beginning to tell.”

Out in the fields, Mr Heath anticipates being able to reduce the amount of ploughing needed to establish new leys and use regular over-seeding to pep up production from long-term pastures.

“TB movement restrictions that caused a build-up in the number of animals prevented us ploughing out leys for a full reseed so we now have a lot of grass that needs improving,” he explains. “That’s what got me looking for a pasture harrow.

“We’ve plenty of opportunity to plough now the cows have gone but it’s expensive,” he points out. “I’d rather see how we can improve existing pastures and extend the life of short-term leys by overseeding.”

Prairial harrow

More substantial

That is what sparked the search for a flexible tine harrow – but he describes the ones he looked at as being a bit lightweight and limited in what they could do.

Those impressions were reinforced when local machinery dealer Stephen Lowe at Border Plant Sales near Sandbach drew his attention to the new Prairial harrow imported by Willow Farm Machinery.

“It looked a lot more substantial, for one thing, and I liked the idea of the slitting knives for aerating the sward and cutting through shallow compaction,” says Mr Heath. “Although we have some very light, sandy land at the bottom of the farm, up on the banks it’s pure blue clay that gets panned in the top inch or so and lies very wet because the water can’t get away.”

In one pass, the Prairial will do the job of an aerating slitter while levelling mole hills, pulling out thatch from the bottom of the sward, breaking the surface and, when required, putting down seed to maintain a decent proportion of productive species.

The implement was used for about 20ha of overseeding last year with good results. It also made its mark repairing damage around a gateway caused by silage trailers running through to an adjoining field, and where bale stacks left bare patches.

“A contractor friend of mine rented the machine to repair ground poached around ring feeders on a nearby farm,” Mr Heath adds. “It also did a brilliant job spreading, levelling and then seeding the spoil from a ditch cleaning operation, and also the soil we put into a low spot when the silage clamp was extended.”

Vital statistics

  • The Prairial is imported from French manufacturer Carré by Willow Farm Machinery in four sizes from 2.5m to 6m. The 2.5m and 3m versions priced £5,700 and £6,490 have a rigid frame; folding wings are on the 4.5m and 6m models, priced £12,600 and £16,200.
  • A Stocks FanJet spinner costs £1,300; a pneumatic TurboJet system with ground drive is £3,400.
  • Reversible slitting knives on 80mm x 12mm flat spring steel carriers are standard but they can be replaced by harder wearing, non-reversible carbide tipped tines or by double tines for more intensive slitting. The knives are spaced 250mm apart as standard but this can be reduced to 200mm.
  • The same carriers are used for the scalloped levelling blades and regular 80mm grass tines bring up the rear. For additional scarifying action, the Prairial can be equipped with a rear linkage to carry a grass harrow.

Remedial situations

Also, from what he has seen so far, Robin Heath is confident of putting down a new ley after cereals without having to plough – two or three passes over the stubble, with the seeder engaged for the final pass, should do the job, he reckons. In remedial situations, the Prairial’s reversible knives help break up rough ground, the levelling blades drag soil into the hollows, and then the flexible tines finish the job by levelling and working-in the seed, which is spread from “splash plates” positioned between the front row of tines.

The tines themselves are set at a trailing angle on their flat spring tine carriers so on pasture they tend not to pull up any clods. Working depth is adjusted by altering the angle of the spring tines that carry them and which allow the knives to bounce up and over any stones.

Similarly, Mr Heath observes, because the levelling blades are mounted on the same type of tines, the resulting vibration discourages bulldozing of material.

Lifting or lowering the implement’s two support wheels alters the pressure on these elements and consequently how aggressively they work the surface.

The 3m Prairial is plenty big enough for a decent work rate because it benefits from being operated at a good speed. Besides, it ensures stability on the steeper banks, whether operated on the farm’s elderly Zetor or new Landini 5-110H tractors.

“It’s already proving a handy tool for quickly patching up damaged areas and getting them back into production for minimal cost,” says Mr Heath. “I’m looking forward to seeing how the grass responds after we’ve harrowed everything in early spring – and to using less fertiliser by improving tired pastures with some new grass.”

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