Doubling rows doesn't double yields. But there's enough of a yield kick to tweak farmers interest about twin rows.

The idea of planting crops in double rows certainly isn't new. It's a concept that some folks have been tinkering with for nearly 30 years.

The difference today is that technology and plant genetics have caught up with twin rows' potential to increase yield. Modern equipment can stagger the seed spacing row-to-row to maximize the yield potential. And some new hybrids yield better in twin rows than they do in single rows on 30" centers.

Planting two rows 7.5" apart on 30" centers isn't much different than planting 15" corn or soybeans. You just don't have to buy a whole new line of equipment to take advantage of the increased yield potential.

With twin rows you spread out the plant population and reduce stress,” says University of Nebraska ag engineer Paul Jasa. He's been testing twin rows planted with a drill since 1996.

“The idea with the drill is that most farmers are more likely to use one to test twin rows than they are to buy a different planter,” he says. “While we have seen positive results with the drill, there's no doubt you would get more stress relief with planted twin rows.”

In Jasa's trials, twin rows haven't always outyielded single rows, but the yield curve increased more sharply with twin rows as plant populations increased. “That was true even in dry years when you'd expect the extra plants to lower yields,” he says. “To me, it just shows the power of twin rows to reduce stress.”

In central Nebraska, fertilizer dealer, farmer and planter tinkerer Gene Carstens has been studying the potential of twin rows since the mid-'70s. He's convinced that agronomy and technology have now come together to express twin rows' true yield potential. He's built two planters for his own farm and for his First Ag, Inc., customers to test the theory.

But to Carstens, twin rows are about more than just yield. And they aren't the total answer themselves. “Our goal is to increase farmers' bottom lines through better yields, and attack other agricultural issues at the same time,” says the Minden, NE, farmer and business owner.

Carstens believes twin rows are best used in a strip-till planting system that includes deep banding phosphorus and potassium with anhydrous while building strips, followed by a healthy dose of starter fertilizer at planting. Additional nitrogen is sidedressed either mechanically or through irrigation.

“We're seeing yields of 250-300 bu on ground where corn averages 180-200 bu,” he says. “But we're doing it with an environmental approach that emphasizes nutrient management and conservation tillage.”

Seven farmers tested Carstens system in 2002 in test plots that ranged from 20 acres to two center-pivots of corn. “On irrigated fields with planting populations of 34,000-35,000 seeds, we saw an average increase of 25 bu or better,” he says. “We basically harvested 10.2 bu for every 1,000 seeds planted. The yield difference probably could have been higher. It was a very dry year and the pivots couldn't keep up with the crop.”

While many farmers have seen significant yield increases, some have tallied more modest gains. Montevideo, MN, farmer Steve Nokleby has experimented with twin-row corn for four years and has basically seen yields match those of single-row 30" crops.

“I originally built my own twin-row planter by bolting two together to create 7.5" spacings on 30" centers,” he says. “But I couldn't get the units set to stagger the seed correctly. In the winter of 2002, I bought a used, Kinze prototype twin-row planter and rebuilt it for the 2002 season. It staggered the seed correctly, but yields still averaged in the 160- to 180-bu range with seed populations of 32,000-35,000. And we had pretty near ideal growing conditions.”

Even without yield increases, Nokleby believes the system has merits. “We'll keep experimenting and I think eventually we'll see yield increases to justify the equipment,” he says. “The thing I like about twin rows vs. single narrow rows is that I don't need to buy a whole new line of equipment. I can harvest my twin rows with my standard eight-row corn head instead of buying a narrow-row head.”

While twin-row pioneers built their own planters, interested farmers today can buy planters right off dealers' lots. Great Plains Manufacturing, Inc., Salina, KS, offers several widths of drills, up to 40' wide, with singulated metering systems. The twin-row units can be used to plant a variety of crops. That's the case with twin-row Monosem planters, sold by ATI, Inc., in Lenexa, KS. The company offers a number of twin-row models, including a 12-row unit.

Both companies have found strong interest in their planters from farmers coast to coast and all areas between.

“Quite a few dairy farmers on the West Coast have bought our twin-row planters. And farmers on the East Coast use them for vegetable crops as well as corn and soybeans,” says Tom Evans, vice president of sales for Great Plains. “We're also starting to see quite a bit of interest from cotton and rice farmers.”

The difference between single- and twin-row corn plants is dramatic, says Evans. “We measured stalk diameters last year. In the same field with the same hybrids at the same population, the average stalk diameter of plants in the single rows was 5/16"; in the twin rows it was 1 1/16",” he says. Nebraska's Carstens has seen similar differences in his comparisons.

“We found the root mass of the twin rows was two to three times bigger than the single rows,” Evans says.

Monosem planters originally found a strong twin-row market among peanut farmers, according to ATI's Don Niehs. “Those same farmers also grow corn and soybeans and started asking why the planters wouldn't work there as well. Our customers also have seen yield increases in crops such as field and silage corn, soybeans cotton and milo,” he says.

Planters sold by ATI match European technology (the Monosem vacuum planter units) with Midwest-sized equipment. Farmers thinking about buying twin-row planters need to be ready for sticker shock. “You need to remember, you're really pricing a 24-row planter,” Niehs says.