The originator of the expression "if you only do what you've always done, you'll only have what you've always had" could have been thinking about weedkilling when he coined the phrase. Weeds in whatever shape or form are a headache for farmers and growers and the traditional method of treating them is to bring out the sprayer. Be it an ATV-mounted sprayer, a tractor-mounted spray rig, a trailed unit or a dedicated self-propelled sprayer, the way to treat weeds has become a question of blasting a powerful chemical onto the weed leaf.
Unfortunately, despite spraying's elevation into something of an art form thanks to high-tech nozzles and holders, stringent government regulations and all manner of electronic GPS systems and technical wizardry this practice has had an increasingly bad press of late, due in no small part to reports of waterway pollutions, complaints (and legal cases) from members of the public over airborne chemicals, and non-target spray issues.
Added to this is the weather factor - wet and windy days are a regular feature in the UK and put good spraying days at a premium, as farmers and spray operators desperately work to protect their valuable crops from weeds. With a small and unpredictable window in which to spray chemicals, operators race against the clock to get spray tasks done and dusted while the weather's right.
Turn over a new leaf
"A farmer with a rabbit problem wouldn't try to shoot them with a pea shooter," says Steve James, sales manager at Broadwood International. "Similarly in certain applications a farmer with a weed problem shouldn't really be trying to kill those weeds by applying chemical to the top of the leaf. Granted, the sprayed-on weedkiller will be absorbed in time by the weed, just as enough peas fired at a high enough velocity may eventually kill the rabbit.
But he's far better off applying weedkiller to the vulnerable underside of the weed's leaf, or on the stem, where nature has provided a soft underbelly - just perfectly made for a rotary weedwiper." Turn over the leaf of any plant and generally what you'll observe is that the underside has a far duller, rougher appearance than the often smooth, glossy topside.
Droplets deposited onto the upside of a leaf will sit on the surface for longer and roll off far easier than those applied to the stem and underside of a leaf, where nature has created a far more receptive surface. Therefore less chemical needs to be used to permeate the leaf, and the chemical absorbed by the plant has a far more effective result.
"This is where a rotary weedwiper comes into it's own," says Mr James. "By spreading the lethal roller surface smothered in a weedkilling chemical up the stem of the weed and onto the underside of the leaf, the weedwiper hits the weed much quicker and more powerfully than the sprayer ever can, as well as leaving the underlying crop unaffected by a non-selective herbicide.
Glysophate chemicals such as Round-Up work on a touch principle, so the weedkiller is working it's way into the plant's vital streams the moment it touches the leaf." This process allows for a more targeted approach to weedkilling and - as an added bonus - uses a lot less weedkiller than the spraying principle.
So how does a weedwiper actually work?
Weedwiping is an incredibly simple process, and is one that in contrast to spraying doesn't require much in the way of training or skill; it's just a question of selecting the correct height between the target weeds and the crop or grass, common sense and an eye to ensure that enough weedkiller is being applied to the roller.
The Wessex Rotowiper is a simple though perhaps unusual-looking machine, and consists of a carpeted, ground-wheel driven roller that rotates in the opposite direction to travel, sitting between two large diameter wheels.
Hitched to a standard ball hitch, the Rotowiper can be adjusted for wiping height via a simple thread system on each side, meaning that only weeds and plants tall enough to come into contact with the set roller height are treated, and not the grass or crop at ground level. A 45 litre chemical tank and pump sits neatly on the frame of the Rotowiper with a protected hose running from the tank down to the roller, and a remote cable runs from the pump to a hand-operated switch on the ATV, allowing the operator to switch the pump on and off as he requires, adjusting chemical application rate dependent on number of weeds to wipe and size of weed. "We recommend that the operator adds a small amount of foaming agent to the chemical tank to enable him to gauge just exactly how much chemical has been applied to the roller," states Mr James.
"There should be a small amount of harmless foam spread evenly across the width of the roller at all times, and by monitoring the amount of foam on the roller the operator can switch the pump on or off to adjust chemical application as necessary." The other benefit from using a foaming agent is that rather like using a blob marker when spraying, it's easy to see where weedwiping has been carried out.
Livestock friendly A popular application for using a weedwiper in contrast to a sprayer is in a paddock or pasture. "Sprayers used with a boom to kill off weeds don't differentiate between weeds and clovers, which are often sown to augment good grazing for cattle and horses." Mr James points out that although selective herbicides won't take out grasses, they will often kill off clovers; "If you're spraying to kill off weeds on grass you've previously sown with clovers mixed in, it really is a case of undoing all your good work. With a weedwiper you can just clear the paddock of the taller weeds while leaving the grass intact and available for livestock to continue to feed on."
Environmentally friendly One of the biggest down-sides to using a sprayer is the unavoidable drift factor. Even in the faintest of breezes, spray mists can drift and float onto non-target crops and into watercourses, polluting them and creating environmental issues.
Despite extensive government legislation designed to remove these threats, it's a known fact that members of the public see sprayers in a bad light. "Spraying a chemical into the air and onto a plant is obviously a lot less accurate than removing the airspace between the spray applicator and the target plant," say Steve James. "Weedwiping is close-contact, targeted work and is far less intrusive into the atmosphere than spraying, with the added bonus of allowing chemical application in windy weather conditions."
The fact that weedwiping can be performed in close proximity to watercourses has been reason enough for a number of county councils to choose the Wessex Rotowiper over a sprayer for weed control near rivers and streams.
Budget friendly "Of course, the less chemical you're using, the less costs you're having to assign to weed treating. It really is that simple!" enthuses Mr James. "There's an admittedly larger initial outlay for a weedwiper than there would be for a standard ATV sprayer, but the savings in reduced chemical costs will quickly outweigh this.
Added to this is the fact that the Wessex Rotowiper has an extremely simple drive mechanism - a V-belt driven by one of the wheels turning the roller is the only wearing part, and the pump motor runs for far less time than an ATV sprayer. Running costs are absolutely minimal and we know of Rotowipers that have been performing reliably for 7 or 8 years. Not many ATV sprayers can claim that."
The original name in weedwiping, Rotowiper, has just been re-launched onto the UK market under the quality Wessex banner, and carries the full support of the Broadwood brand. Unique features include a spiral-welded rotor for maximum strength - "essential for some of the larger widths the Rotowiper is available in" according to Steve - and a unique carpet that is the only one of it's kind in the entire world that has been specifically designed for the demands of weedwiping. Made from a special looped fibre that passes through the rotor twice and retains the chemical droplet until contact with a plant, the UV-treated, rot-proof carpet is constructed with glue-less technology, while stainless steel fixings secure it to the rotor. "The Wessex Rotowiper has been designed to provide a long, trouble-free service life," says Steve James. "With minimising costs high on everyone's agenda, that's the way it should be."
For more information on the Wessex Rotowiper contact Broadwood International on 01420 478111, or visit their website; www.broadwoodintl.co.uk
Hampshire GU35 9HH
T 01420 478111
F 01420 483000