From the road you could see the flames. Drivers speeding by did a double take, then stopped and backed up to watch as farmer and Team FIN member Scott McPheeters put a torch to his corn crop.
What looked like an uncontrolled battle between man and nature was actually a calculated strategy to control weeds and grasses.
The technology is called crop flaming. Propane-fired torches mounted on a toolbar shoot foot-long, 2,000F flames. One burst for a tenth of a second at the base of the crop is claimed to kill weeds and grasses by burning the sap and rupturing the cell structure. "It's like banding with fire," says McPheeters, who farms outside of Gothenburg, NE.
Rekindled flame. Crop flaming was first introduced in the early 1930s. But use was dampened in the 1960s with the advent of herbicides.
Recently, however, the rising costs of chemicals and growing concerns for food safety and the environment are rekindling interest in this age-old practice, according to Tim Morse, sales manager at Flame Engineering. "We've received thousands of calls between February and July from farmers inquiring about our ag flamers. When chemicals don't work in spring or summer, they're looking for a quick fix."
McPheeters wanted to try the flamer after contracting to grow popcorn without the use of chemicals. He wanted a backup to kill weeds and grasses if cultivation didn't work. Flame Engineering agreed to let him test its Red Dragon row crop flamer for Farm Industry News.
The test. McPheeters had the choice between a turnkey system-complete with a propane tank and cart, an 8-row toolbar, and torches and a skid to mount them on - for $11,200, or a kit for $5,743, which excludes the tank, cart and toolbar. If the burners are mounted on an existing cultivator, the 8-row kit is available for $3,743.
McPheeters went with the $5,743 kit. He bought a used anhydrous tank and cart from his fertilizer dealer for $400. For an extra $200, the dealer flushed the tank and changed the valves to make it work for propane. McPheeters also salvaged a 30-ft. toolbar for $150. With labor, costs totaled about $7,500.For the record, the company recommends rollover protection for the tank, both on the frame and at the valve area.
McPheeters didn't doubt that flaming would kill the weeds and grasses. But he feared it would kill the crop. "Our biggest question was, How big does the corn have to be to protect it from damage?" The company claims that as long as the crop is taller than the weeds and grasses and past the early growth stage, flaming will not hurt the crop.
McPheeters waited until June 1, when the grass was as thick as a pencil lead and the corn as thick as a Magic Marker body. He started with his field corn first, because it was growing the fastest. The second week he moved on to his popcorn acres.
The results. In places where there were both grass and broadleaves, the flamer worked well on grass but not broadleaves, McPheeters reports. At the time of application, with the corn being 10 to 12 in. tall and some of the broadleaves 8 to 10 in. tall, the flame shot under the broadleaf canopy and, as a result, didn't burn the broad-leaves. "If you use it for grass, where the stems are small and the leaves are low, it works great," McPheeters says.
As a result of the test, he plans to buy the flamer. But he will limit its use to grass from the start, except in areas where the broadleaves are one-third as tall as the corn to ensure that the flame will burn the broadleaf canopy rather than shoot under it. He will continue to cultivate all of his acres and use chemicals on his field corn. He states, "It's just another weapon in my arsenal."
He says flaming is safer to the crop than chemicals if used as directed and is less weather dependent than cultivation because you can go in sooner after a rain and not worry about traction or resetting the grass in the moist ground.It's also cheaper. Row-crop flaming uses 4 to 7 gal. of propane/acre. McPheeters figures that the cost of the single application was between $5 and $7/acre, with propane priced at $0.75/gal. Chemicals would have cost twice that. "So you can still flame several times and still be under what it takes to treat with some brands of corn chemicals," he says.
However, Flame Engineering is quick to point out that the product is not intended to replace chemicals. And the larger, more deeply rooted weeds may require repeat applications. "In a heavy weed pressure year, there's no one answer," Morse says. "Flaming is one option."
Other companies market flamers. The technology can be used on up to 40 crops, including soybeans. For more information, contact Flame Engineering Inc., Dept. FIN, Box 577, W. Hwy. 4, LaCrosse, KS 67548, 800/255-2469.