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Our tests target narrow-row corn and high-speed harrows These
are two of the test plots FARM JOURNAL planted in 1999 under the
direction of field agronomist Ken Ferrie. Established in cooperation
with Crop-Tech Consulting, the plots are planted in central Illinois.
Special thanks to the following cooperating farmers: Charles Sprague,
Neil Nichols, Terry Ferguson, Tim McCorkle and Gerald Benge.
New Routes to Narrow-Row Corn The drive to plant narrow-row corn without placing the seed in tire tracks or having a tire run over the row led FARM JOURNAL to this set of test plots. "Our work in other narrow-row corn plots had shown the [negative] impact wheel tracks and tires can have on yields," says Ferrie. "We are trying to sidestep those problems and measure true yield differences." "We also are looking for a way to get narrow [corn] rows and a higher ear count without requiring a bunch of new equipment," he adds. The special plot planter from Great Plains Manufacturing can plant 30", 15", and 7" twin rows. The front bar, carrying six 30" rows, is three-point mounted. The back bar, with six rows, hooks on behind. Flipping the hitch determines whether it joins in to plant 15" rows or a pair of 7" rows on 30" centers. "The 7" rows are 3 1/2" to the side of where the 30" row would normally be, so it's never in a wheel track or run over," explains Ferrie. "Four of the 15" rows were run over by the rear planter and two of those rows were also planting into the wheel track of the tractor. That's why the yields of the 15" rows sacrificed ear counts and yields were lower." Being on 30" centers provides an advantage for the twin rows: They can use the same sprayer, sidedress equipment and corn head as the 30" rows. "There's no big extra equipment expense, so it removes the economic pressure to yield more," says Ferrie. Even so, the first-year data shows the twin rows posting the highest plot yields - up to 15 bu. over the 30" corn. The 15" yields were higher than the 30", but notably lower than the twin rows. Great care was taken to match the sprockets so the three row spacings were planted at the same populations. No matter what, narrow rows pose a challenge for planting accuracy because the meter runs too slowly for optimum performance and can create skips and uneven distribution. "It's a delicate balance between running the planter fast enough to get the meter's rpms up, and not running the planter so fast that it causes row unit bounce and results in uneven emergence," explains Ferrie. To ensure accuracy, we had the finger-pickup meter calibrated for the seed, speed and row spacing being used. The planter was designed to put on starter and insecticide. Starter for the 30" rows went on at full rate. The 15" rows received a half rate, and the twin rows were fed a full rate, between the two rows, so all received the same rate per acre. "We know starter was important to the overall results because a round of 30" rows without starter yielded almost 20 bu. less," says Ferrie. Insecticide was applied at full rate in a 7" band for the 30" rows. A half-rate went on the 15" rows in a 7" band (which supplies the same rate). The twin rows received a full rate in two overlapping 7" bands that created an overall 10" band. Stalk borer and corn borer invaded the entire plot. The 15" suffered the most. Eventually, the heavy pressure in the 15" triggered a post spraying of the whole field (to keep things fair, all row spacings were sprayed). "This experience definitely shows us it's important to put the insecticide rate on a per-foot-of-row basis rather than a per-acre basis," says Ferrie. Other differences between the row spacings include:
Tillage Tools Sidestep Soil Density Problems Two new-style tillage tools fly over spring fields, leaving the soil level and ready to plant. And ongoing FARM JOURNAL field tests show that the pair complete their work without dramatically changing soil density and post promising yield results. We tested the two machines - the Spiral Reel Stalk Chopper from McFarlane Manufacturing and the Rotary Harrow from Phillips - to evaluate their ability to help maintain uniform soil density. The two, which work best at 8 mph to 10 mph, do much of the work of field cultivators without creating a horizontal tillage layer or greatly disturbing the soil. "A horizontal tillage layer shortchanges yields through a sudden density change. These machines level the seedbed without doing that," says Ferrie, who tested the machines. "Even if a field is ripped in the fall, it takes only one misstep to create a density problem," he adds. "Pushing field conditions a bit and causing compaction, or creating a horizontal tillage layer can override the advantages of ripping in the fall. It's easy to cost yourself 5 bu. to 7 bu. of corn, especially in heavier soils." New-style tillage tools offer a way to avoid that. Spiral reels run upfront on the McFarlane, chopping residue and loosening soil without burying residue. A five-bar flexible spike tooth harrow marches behind the reels, stirring, leveling and firming the field. A spreader board brings up the rear, leaving the field level and residue evenly distributed. The machine is best suited as a spring tool (following some type of fall tillage). It can level chiseled, ripped or plowed ground and needs loose soil to run well. The Phillips uses an interlocking tine assembly to do its work. Patented in Australia and built in Canada, it has a cable running down the center of the heat-treated tines. It can be used as a stand-alone tillage tool in the spring in bean stubble - to dry the soil for planting. It doesn't move as much soil as the McFarlane, and the field needs to be relatively smooth before it operates. In 1999, the Phillips was tested at two sites where water was at a premium. Those conditions showcased the importance of uniform density. Yields posted with the harrow were about 10 bu. better than those recorded in adjacent plots using a field cultivator, even though the entire field was deep ripped the previous fall. "The difference in the corn was so obvious that it looked like a hybrid change," says Ferrie. "Density problems made the field-cultivated side run out of water, which sped up crop maturity. By harvest, that corn was 2.5 points drier. That's a big difference." Water wasn't an issue at the McFarlane test sites, making the comparison between it and a cultivator less dramatic. Still, it posted strong performances. Downsides
are that the machines can impact the herbicide program. Unlike a
field cultivator, they don't take out the first flush of weeds.
Plus, the planter needs to be fitted for high-residue conditions.
"Weed control and insect scouting have to be similar to what you'd
use for no-till," Ferrie says. FARM JOURNAL
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April
2000
McFarlane Mfg. Co. Inc. • 1259 S. Water St. • P.O. Box 100 • Sauk City, WI 53583 • 608-643-3321 • 800-627-8569 |