John Russnogle 1

November 1, 2007

9 Min Read

When farmers tell Mike Janssen they're frustrated about bean yields, his answer makes them smile. He tells them they're insane. “That's when you keep doing the same thing over and over but expect different results,” says Janssen, from Hooper, NE.

And he's a little frustrated himself. He believes farmers leave a lot of yield in the field because of old habits that ignore new technology. To prove the point, he made a few cultural changes in the 2007 variety test plots he grows for Golden Harvest. The result was 90+ bu. soybeans on six of 12 NK Brand varieties on non-irrigated ground.

The same field averaged 58 bu. and 60 bu. in 2005 and 2006, respectively. The highest yield in this year's 650-ft. test plot was 94.4 bu. The lowest was 74.5 bu.

There's nothing exotic about Janssen's high-yield ideas. No snake oil or foo-foo products, as he likes to call them. “Most of the yield increase is simply cultural practices that protect the yield potential,” he says. “The genetic improvement or big yields is there; farmers just aren't realizing the potential.”

Yields are improving, however. “When I first came to Iowa State University (ISU) in 2003, farmers complained about 40-bu. soybean yields,” says Palle Pedersen, ISU Extension soybean specialist. “Now they complain about 50-bu. yields.

“We're starting to prove we can produce high-yielding soybeans across a large number of acres. Iowa should average 52 bu./acre in 2007, and we can increase it even more if we get more people on board. Iowa has not averaged above 50 bu./acre the last three years. Everyone should be able to raise soybeans that yield in the high 50s-60s,” says Pedersen.

Since 2003 Pedersen has focused his research on high-yield soybeans with checkoff funds from the Iowa Soybean Association. Janssen studied under Pedersen as a graduate student.

Growing high-yield soybeans is a nurturing process, different than the pedal-to-the-metal mentality used for pushing corn yields, according to Kevin Coey, president of AgSCI and owner of F.I.R.S.T.,an independent farmer organization that plants test plots annually to check yield potential for corn and soybeans.

“Soybeans are less dependent on environmental conditions than corn. In our tests we see soybean yields move up and down in a pack,” Coey says. “Hybrids, on the other hand, tend to have an individual niche that they thrive in. And there's more genetic diversity in corn,” he says.

The soybean nurturing process eliminates yield-reducing stresses such as weed pressure, insect infestations and diseases, such as white mold, SCN, sudden death syndrome or pod and stem blight, according to Coey. “It's important to have a field history of diseases that will reduce yields and then manage the crop to minimize the effects,” he says.

That's a season-long process, adds Pedersen. “It doesn't take a lot of mistakes to lose yield,” he says. “Soybeans are very sensitive to stress from weeds, insects or diseases. Any treatment decisions you make should be based on crop scouting and integrated pest management recommendations. It's critical that you keep the plant running at high capacity through July, and then it's up to Mother Nature to provide some August rains to fill out the seeds.”

Not surprisingly, Janssen will tell you that high yields start with seed. “Variety selection accounted for 21% of the yield increase we saw in our test plots,” he says. It's easy for farmers to figure out what varieties are best suited for their area. Seed dealers have that information and, of course, are more than willing to share. It's cutting the check that slows farmers down.

“Farmers tend to select soybeans based on seeds/lb. and cost/bag,” Janssen says. “Variety selection is third. They want the high seed count because it lets them plant more acres. But when you select a variety with tiny seeds, it yields tiny seeds.

“You need to look for a variety that will produce lots of large seeds to get top yields. The highest yielding variety in our plots had seeds the size of marbles,” he says.

Step two in Janssen's plan for high-yield soybeans is the tough one for most farmers. He planted his beans April 18 and figures that adds anywhere from 5 to 10 bu. an acre. “We had beans breaking the ground before some farmers started planting corn,” he says. “The weather was beautiful. In fact, we were wearing T-shirts. Then it turned cold and wet.”

Early planted beans certainly aren't a new idea. Farmers across the Midwest have tested the theory and, for the most part, decided it's better to wait until May. But, Janssen contests that newer crop protection chemicals can offset the risk of damping off and other early season plant diseases and insect infestations, specifically early bean leaf beetle populations.

“You have to manage the risk. We used seed treated with Cruiser-Maxx Pak, an insecticide/fungicide combination,” says Janssen, who works as a technical service agronomist for Golden Harvest, which is owned by Syngenta, manufacturer of Cruiser-Maxx. “Seventy percent of the seed we sell is treated.”

Why early planting? “Soybeans are a source-limited crop. Yield is strongly correlated to the total amount of solar radiation the plant receives,” Janssen says. “Once you understand the physiology of the plant, it becomes black and white what we need to do for higher yields.”

Janssen's early planted soybeans began to bloom by June 1. “That's key,” he says. “As the season progresses, the day length shortens and the light spectrum changes. Yield potential goes down as the quality of the light changes.

“With early planted beans,you're putting together a bigger factory. It allows you to maximize plant growth before soybeans reach the reproductive stage,” he says. “The early planted, high-yield beans had 8-9 nodes before they flowered. I picked up 4-5 nodes that late-planted beans would never get.”

Janssen used a 30-in. planter to seed his plots, but split the rows to end up with plants on 15-in. centers. “Narrow rows are critical for high yields,” he says. “Narrow rows add an estimated 5 bu./acre to the yield.” His planting rate was 170,000 seeds/acre.

A hidden advantage to planting soybeans early, according to Janssen, is you're likely to do a better job. “By the middle of May, when most farmers plant soybeans, they're worn out from corn planting. They drive 8 mph to get the beans in as fast as they can and just want to get done,” he says. “There's a mentality that soybeans are just a rotation crop and not worth the effort to do the best job possible.”

The rest of Janssen's production practices are pretty ordinary, albeit steps many farmers don't use. Fall-applied dry fertilizer assures nutrient levels don't impede yields. Weed control includes a pre-plant herbicide and two applications of Roundup. One aerial application of Lorsban and one of Quilt tank-mixed with Warrior provides in-season protection against disease and insects.

“We had a total of $213/acre in production costs,” says Janssen. “That includes a fee for combining and the premium for crop and hail insurance, but no land charge.”

The math makes you think twice about corn. With 90-bu. yields and $9 beans, you're going to gross more than $800/acre. That still might not justify some of today's ballooning land prices, but it's certainly on par with corn.

“We have to find a way to make soybeans compete with corn or the crop is going to disappear,” Janssen says. “So many farmers want to go to corn-on-corn because of the economics. That's true if you have 50-bu. beans. It's not as lucrative at 75-80 bu./acre.

“Soybeans are a crop that nobody is focused on. Corn is king,” he says. “But there are gobs of opportunity. And in the long term, it's better for both crops to be grown in rotation.”

Adds Coey, “People get excited about corn, but they're starting to understand that a 10-bu. increase in soybean yield is just as valuable as a 30-bu. increase in corn yields. However, they're going to have to adapt new cultural practices and nurture those higher yields.”

So, the biggest impediment to growing high-yield soybeans may be under your baseball cap. “It's hard to think to change,” Janssen says. “We've adapted a different thought process and the result is 90-bu. beans.”

If Corn Is Biofuels King, Tropical Maize May Be Emperor

In terms of biofuel production, tropical maize could be the sugarcane of the Midwest. Its tall stalks are so full of sugar that it is at least one step closer to being turned into fuel than are ears of corn, according to University of Illinois research.

Maize may prove to be the ultimate U.S. biofuels crop. It produces 25% or more sugar as sucrose, fructose and glucose. This sugar is one step closer to becoming ethanol than the starch in corn, miscanthus, stover and switchgrass. These conventional feedstocks must be treated with enzymes to convert them into sugars that can be then fermented into ethanol.

Storing simple sugars also is more cost-effective for the plant, because it takes a lot of energy to make the complex starches, proteins and oils in corn grain. This energy savings per plant could result in more total energy per acre with topical maize, since it produces no grain.

When University of Illinois crop scientist Fred Below began growing tropical maize, the form of corn grown in the tropics, he was looking for novel genes for nitrogen utilization. Early research results show that tropical maize, when grown in the Midwest, requires few crop inputs, such as nitrogen fertilizer, chiefly because it does not produce any ears. It can be easily integrated into farmers' current operations than some other dedicated energy crops because it can be easily rotated with corn or soybeans, and can be planted, cultivated and harvested with existing equipment.

“Corn is a short-day plant, so when we grow tropical maize in the Midwest, the long summer days delay flowering, which causes the plant to grow very tall and produce few or no ears,” says Below. Without ears, these plants concentrate sugars in their stalks. According to Below, Midwestern-grown tropical maize easily grows 14-15 ft. tall building up to a level of at least 25% sugar in its stalks.

The tropical maize at the University of Illinois requires much less nitrogen fertilizer than conventional corn, and the stalks actually accumulate more sugar when less nitrogen is available.

Below explained that sugarcane used in Brazil to make ethanol is desirable for the same reason: It produces lots of sugar without a high requirement for nitrogen fertilizer, and this sugar can be fermented to alcohol without the middle steps required by high-starch and cellulosic crops. But sugarcane can't be grown in the Midwest.

The tall stalks of tropical maize are so full of sugar that producers growing it for biofuel production will be able to supply a raw material at least one step closer to being turned into fuel than are ears of corn. “And growing tropical maize doesn't break farmers' rotation,”Below says.

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