The idea of fluffing up a swath of grass before chopping or baling it may not be new, but there is renewed interest in it. Simon Henley and Peter Hill report.
In the 1960s the Bamford Wuffler was one of several swath-tedders used by farmers to aerate and condition grass crops prior to forage harvesting or haymaking. At a time when most farms still cut their pastures with finger-bar mowers, the action of these machines dramatically speeded up the on-field drying process.
Canadian Agway Accelerator is the only trailed swath conditioner available and
the only one to use crimping rollers rather than tines to condition the crop.
Agricultural trends change and the swath-tedder was superseded by rotary tedding machines like the PZ Haybob, which spread the grass to dry it even faster. Although rotary tedders have developed considerably, their ability to operate effectively in heavy crops in poor weather conditions has been a limiting factor.
Last year, one of the worst summer seasons on record saw UK farmers battling the elements as they tried to make decent crops of hay and silage. Getting mown grass dried was the main concern.
Spreading grass on wet ground and rowing it up again will all too easily result in contamination unless great care is taken with settings and operating speed in restrained. But in these conditions, the ‘new generation’ tedders, horizontal rotor machines designed and built to cope with the rigours of aerating a heavy-yielding crop of grass destined for silage, came into their own.
K-Two Airo uses polyurethane ‘V’ shaped tines to lift the swath without touching the ground and
to condition it without risk to following machinery should one of them break free.
Apart from the Canadian-built Agway Accelerator, which passes the crop between two crimping rollers, these versatile machines use rubber-mounted steel fingers rotating at high speed on a horizontally mounted shaft. They work in much the same way as a vacuum cleaner brush, lifting the grass swath and discharging it between adjustable doors to leave a deep and even swath through which air can easily pass.
Rather than simply picking up and dropping the material, however, the process includes some conditioning effect – the roller machine crimps the stems while the tine devices scrape at the waxy surface. The net result is the same – moisture can escape more easily and the time taken to achieve the required wilt is reduced.
Apart from providing the sole source of conditioning when used in the wake of a non-conditioning mower – which some growers are using to gain output by going wider while minimising capital cost and tractor size – the swath conditioner minimises the risk of contaminating fodder with soil and stones.
Vee-belt driven rotor on the Teagle Super-ted runs on self-aligning greasable bearings and
its steel coil spring tines have retainers to prevent them being lost to the swath after a breakage.
“Machines like the Astwell 170 Swather significantly improve drying rate by aerating the swath and conditioning the grass,” says Clive Jones of Astwell. “But because the job is done in one operation and on a correctly set machine the tines never touch the ground, the risk of soil and stone contamination is very much reduced compared with spreading and gathering again.”
Preparing and shaping a swath for easy pick-up by a baler or forage harvester is another benefit, suggests Tom Teagle of Teagle Machinery.
“Modern swath-conditioners are designed to accommodate a high volume of material and provide great control of the size and depth of the swath they leave behind,” he says. “They work particularly well ahead of modern high capacity balers and forage harvesters, especially our Super-ted units, which feature a high-volume hood design so that a fast working speed can be maintained.”
Adjustable front baffle on the K-Two Airo regulates the degree of crop conditioning effect.
The Agway Accelerator conditioner from the Profitable Farming Company is the odd one out here and not just because it is trailed rather than mounted.
“It uses two rollers, each with 11 interlocking ridges, to bend and crack the plant stems to produce a conditioning action that is more aggressive than conditioning with tines,” says the firm’s Richard Snell. “In field trials the machine has reduced field drying time by up to one day.”
An added feature is that with the optional cross-conveyor installed, grass swaths are inverted as well as conditioned and moved on to dry ground. Moreover, operators can place three swaths alongside one another to reduce the number of passes needed with a baler or forage harvester.