Dan Stevens and his brother Bob aren't strangers to 15" rows. They've been pushing that narrow-row envelope for five years with corn and more than 10 years with soybeans. But now, the Hanley Falls, MN, growers are doing it in a much easier way.

They had been using two John Deere 7000 30", 8-row splitter planters on their 1,100-acre operation. One unit was bolted behind the other to cut row width to 15" for a total of 15 rows. A 30" space was left behind each tractor wheel.

But that somewhat cumbersome system, which worked well, had just worn out. Each planter was 23 years old.

So last year, they streamlined the setup and switched to a new 30' Kinze 3600 planter. “Originally, I wanted to go with 22" rows, but it just made more sense to go with 15". We'd have fewer changes with our harvesting and spraying equipment,” Dan Stevens says.

He squeezed planter units together to get 15" rows, but left a 30" space between the second and third units on one side of the planter to accommodate a tractor wheel track.

“We leave one wheel track when we go down the field and the other when we come back,” he says. “We also have a 60' sprayer to match the tracks.”

Those two end units run on smaller sprockets. “Since those are double the width, they can handle double the plant populations,” Stevens explains. Currently, he's planting at 35,000, up from the old 30"-row days of 32,000.

His planter tools along at 7 mph now, at times even hitting 9 mph without problems. “On 30" rows I'd drop a seed every 6". With 15" rows, I drop a seed every 11.2",” Stevens says. “But to get the ground-driven units to run at their optimum, I need to run faster.” With beans, however, he'll continue to drive at his normal 5½-mph rate.

The move to 15" rows was simple. He wanted to pick up that 5% yield bump that experts say you can count on. “I have no proof I got it,” Stevens says, “but my gut feeling still is that it's the way to go. So, we went cold turkey. We also get good weed control on both corn and beans, and it keeps that second flush of weeds from coming.”

Stevens isn't alone in thinking narrower rows pay off. It's the trend nationally, says Joe Lauer, University of Wisconsin agronomist.

“With corn in northern tier states, we're seeing about a 2% yield increase going from 30" down to 20" rows, and another 2% going from 20" to 15",” says Lauer.

For soybeans, he says the response is similar. However, Wisconsin research points to increased white mold pressure at 7½" rows and a decrease in yield at 30" rows. “So, we're looking at 15" row spacings for beans as an optimum trade-off to manage that canopy,” Lauer says.

Even though narrower rows can pay off, a multitude of management practices need to be in line first, Lauer says. (See story, page 12.)

Mike Toelle and his brother Bob knew narrow rows were in their future and that they had the management skills to make the switch. It was just a matter of time before they pulled the trigger. It meant, of course, new equipment for both planting and harvesting to get what they hoped would be a 5-bu/acre yield advantage. Even at $2 corn, that $10/acre advantage looked pretty enticing.

Last year they finally retired their 33', 7½"-row Flexicoil soybean/wheat drill and their 10-year-old 30', 30"-row John Deere corn planter. They replaced them with a new John Deere 1780 40', 20"-row planter to handle both corn and beans.

“We wanted to control the depth and meter our seed more closely,” Mike Toelle says. “We hoped we'd get a better stand with less seed cost.”

Although they didn't make side-by-side comparisons with the old planter, Toelle says they're convinced the change was worth it.

“We were happy with our stands and emergence last year, and we ended up with the best yields we've ever gotten,” he adds.

Corn yielded 150-175 bu/acre and soybeans averaged 40-45 bu/acre at their Browns Valley, MN, operation.

“Some argue that 30" rows yield as much as 20" rows. But to me, it's common sense that if plants are spread out more evenly, they'll use nutrients and moisture better,” Toelle says.

With the Flexicoil bean drill, the Toelles planted about 185,000-195,000 seeds/acre. If fields were trashy, they increased the seeding rate. With the new planter, they've dropped their rate to about 170,000 seeds/acre. That 5-10 lbs less seed/acre cut their soybean seed cost about $2-3/acre. And that's a conservative estimate, they say.

“We now have one planter instead of two, although it's worth about the same as the other two combined,” Toelle says. “But with one unit, we only need one man and one tractor instead of two.”

In addition, the new planter will cover about 25 acres/hour compared to just 18-20 acres/hour with the older unit. “We're definitely going to be more timely with planting,” Toelle says.

The Toelles still no-till wheat with a 30' John Deere 1850 drill on their farm of more than 2,500 acres.

To prepare for the switch to 20" rows, they had purchased an 8-row, 30" corn head a year earlier. They slid the units together to 20" and added four new units to make a 12-row, 20" head. To rework the head, including adding snouts, they spent $12,000 out of pocket.

The new planter also has two, 250-gallon liquid starter tanks on it. The Toelles will likely add tanks to the tractor, too, and apply all their phosphorus in spring rather than fall — at least that's the plan right now.

This year they'll also experiment more with variable-rate planting. “We tried it on some test strips last year to see how it worked,” Toelle says. “We took some beans down to 150,000 and up to 180,000 seeds/acre and didn't see any big yield difference. But we're not confident in our results.

“We tried to find spots in the field that were consistent to run our variable-rate tests. Eventually, we plan to take the population down on knobs and on poor parts of our fields,” Toelle says.

Their goal is to grid sample, map and move toward variable-rate planting throughout their operation.

But for now, they've decided to take it a step at a time. “We're new at looking into variable rates,” Toelle says. “First, we need to get narrow rows down. We'll learn one thing at a time.”

Considering Narrow Rows?

Before entering the narrow-row era, consider this advice from Joe Lauer, University of Wisconsin agronomist:

  • You should farm a large total acreage of corn and soybeans.

  • You should look at other management aspects of your operation first. “You can have a 30% swing just on your hybrid selection,” he says. “There are lots of things to line up before you go after that 4-5% gain with narrow rows.”

  • Populations should be above 30,000 plants/acre for corn.

  • Once you have management options such as hybrid selection, rotation, plant density, planting dates, pest control and soil fertility nailed down, he says you should be producing corn over your entire farm at a yield level of 160 bu/acre or more.

  • You should plan to depreciate additional equipment costs over the life of your farming career. “Either your present equipment line should be worn out, or narrow rows work best for younger farmers who have more time to depreciate equipment,” Lauer says.