The use of pressurized water as a cutting tool has come full circle.
It was used extensively to power away earth during the 1850s California Gold Rush. Now, after being adapted and refined to carry out high-tech, precision cutting of metals and other industrial materials indoors, the technology has turned back to the ground.
Why it matters: Participants in the recent FarmSmart Expo learned it’s possible to retrofit their existing planters to eliminate soil-to-coulter contact and instead have the cut made entirely by pressurized water.
Jeff Martel is applications manager for I-Cubed Industry Innovators, a company specializing in “high accuracy precision robotics.”
Martel told the FarmSmart audience that when he first made connections with an Australian proponent of what’s known as aquatill a few years ago during a waterjet-cutting conference in the southeastern United States, he didn’t think the concept was possible. He thought the amount of water needed and the energy requirements of a planter-mounted pump would be too much for the technology to be adapted for crop use. But as he explored the idea, those concerns were eased.
The Australian, Greg Butler, made the voyage north to join Martel in co-hosting the most talked-about session at the 2018 FarmSmart Expo, held July 12 at the Elora Research Station of the University of Guelph.
Butler said if only horsepower and water requirements are looked at, the payoff might not be there.
The partially retrofitted planter on display at FarmSmart, which made repeated passes through a patch of wheat stubble to demonstrate the technology, featured a larger-than-necessary 50-horsepower pump supplying water to three waterjets, one waterjet per row. Martel said it was necessary to supply only 12 horsepower per row.
The planter deposited seed after each jet and a soil-closing tool pulled up the rear. Martel said that i-cubed aimed for 100 to 160 litres per hectare (40 to 65 litres per acre) of water in the prototype.
But minimum-till farmers have considerations beyond horsepower and water requirements to think about, said Butler. First, increased speed increases the cutting effect, and secondly, the technology cuts wet residue more effectively than dry residue. That means farmers can drive faster while planting and keep their tractors running through darkness and early morning when dew often halts the work.
Butler, who has secured government funding for an Australian university study into the technology on behalf of the South Australia No-Till Farming Association, acknowledged to conference attendees that his knowledge is based on crops common to his region, such as wheat, sugarcane and cotton … and not the corn/beans/wheat management regime that dominates southern Ontario.
He stressed that in Australia, leaving lots of residue is a widespread practice due to its moisture retention benefits. Getting through that residue at planting time without allowing it to impede germination is critical.
Butler added the study’s findings have been encouraging in more than one respect. In his region, an effect known as “hair-pinning” of residue in a coulter-cut seedbed was completely eliminated and that translated into significant germination rate increases.
In the sugarcane-growing region along the east coast’s Great Barrier Reef, where eco-tourism trumps agriculture in economic and political influence, farmers were intrigued about the potential for integrating precise nutrient placement through the waterjet, instead of risking nutrient loss to surface runoff, and ultimately endangering the ecologically sensitive Great Barrier Reef.
In North America, I-Cubed is among companies specializing in industrial-scale waterjet cutting, which have begun exploring agricultural applications. Martel said the Stoney Creek-based firm has filed for some patents related to planting.
In Australia, the South Australia No-Till Farmers Association hopes to see an aqua-till enabled planting unit equipped with a 270-horsepower pump available in 2019.
Researchers are still working out what liquids can be run through the waterjet pump. Martel expected that a commercial unit would offer a means to apply liquids directly through the waterjet pump and through an attached injection unit.
He said one added innovation could rapidly alter the future of waterjet use.
“I would love to see a fertilizer company say, ‘we’re high-pressure certified.’ Even being able to run one small additive through the pump could change everything.”