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6 reasons beans are back

The evidence is mounting that soybean acres will get a bump in 2013. The reasons may be more agronomic than economic, say farmers and crop specialists.

“Corn will always have more value per acre simply because it yields so much more,” says Mike Schrum, a farmer and agronomist for West Central Cooperative, Grand Junction, Iowa. “But in a year like 2012, the agronomic benefits of crop rotation really showed up.” Those can quickly become economic ones, he adds.

Here are six reasons why you may be planting more soybeans in future years.

1. Continuous corn took a hit

Exactly why is debatable, but Schrum uses his own family farm as a good example. They have fields that have been in continuous corn for five years and others that have been in a 50-50 rotation with soybeans. The continuous corn yields have lagged rotation yields by about 10 bushels an acre — generally acceptable, given the market incentives for corn.

But in 2012, the yield hit to continuous corn was significantly harder. Rotation corn yielded about 150 bushels per acre, while continuous corn was near 100 bushels an acre.

Other farmers and university research fields saw continuous cornfields take big yield hits, too. Shawn Conley, University of Wisconsin Extension agronomist, says continuous corn in his state generally lagged rotational corn yields by 30 or more bushels an acre in 2012.

“Some of the reasons for this are still unexplained,” Conley says. “It could be because of the buildup of plant diseases in continuous corn. Soybeans need less water than corn. In a dry year, those things really pop out.” (See number 3.)

2. Well-managed soybeans held up

Again, Schrum's family farm in central Iowa serves as a good example.

“We apply some high-intensity practices to our soybeans,” says Schrum, “including fertilizer, micronutrients, and fungicides. Prior to 2012, we'd been averaging 56 to 57 bushels an acre,” he says. “In 2012, it was 52 bushels with those high-intensity practices.” He says nearby fields without those practices yielded about 30 bushels per acre.

In Wisconsin 2012 soybean tests, soybeans were amazing, says Conley. In one location in the southern part of the state, just .3 inches of rain fell during an eight-week period from May to July, and some plots still yielded over 80 bushels per acre.

“If you get the beans planted early and get good early weed control, that's when they do really well,” he says. “We don't normally think of soybeans as a deep-rooted plant, but we saw some soybean roots go down 36 to 48 inches, following the water down all season long.”

3. Corn sucks more H20 than soybeans

Soybeans tolerate dry weather better than corn. One issue is the biomass comparison to corn. The pounds of grain produced and the vegetative matter of the growing crop are less with soybeans. Soybeans also require less soil moisture reserves to support the growing crop.

Plus, continuous corn tends to require more tillage, sometimes to alleviate soil compaction and sometimes to manage the residue volume of a continuous corn crop.

Schrum says deep-ripping soils is a common practice with continuous corn. In 2012, that simply dried soils quicker and deeper than minimal or no-till. He tells of a field of one of his co-op clients where he could see right to the row where deep tillage was performed and how that corn suffered earlier and more severely in 2012's heat and drought.

Wayne Fredericks, Osage, Iowa, says he suspects that half-buried stalks in tilled cornfields act like a wick, bringing moisture to the surface where it is lost.

4. Rootworm abounds

A few years ago, corn was thought to be the easy crop to manage, with the most genetic crop technology for pest management. Now, that thought seems naïve. Nothing's ever easy.

Corn rootworm is one of the best examples. These pests find a way around every technology that comes along, including the first-generation built-in Bt controls. Crop rotation from corn to another crop (such as soybeans) is now back in style as one of the best ways to manage this pest.

“If you aren't getting full rootworm control from whatever technology you use, it really impacts moisture and nutrient uptake in a normal year and more so in a dry year,” says Tracy Blackmer, director of the Iowa Soybean Association's On-Farm Network.

In a wet year, intact roots can compensate for some corn roots severed by rootworms. In a dry year like 2012, the impact of root feeding is much more significant.

Besides rootworm, there are other plant health issues that build up over time with continuous corn, including other insects and plant fungal diseases.

“Rotating crops is good, and 2012 made that case very strongly,” Blackmer says.

5. Soybeans can survive a sledgehammer

Soybeans are tough, and 2012 really brought that point home. Conley calls soybeans the sledgehammer crop.

“You can hit them hard, and they will bounce back,” he says. He points to the long flowering window of soybeans, which is six weeks or more.

“They can wait for a rain and then put on more flowers, more pods, and more beans,” he says. “Corn's flowering window is only about a week.”

Fredericks makes a similar observation. “With soybeans, you bring another month into the picture,” he says. “Corn depends on July weather. Soybeans can be made on August rain. If you plant both crops [which he does, in an every-year 50-50 crop rotation], it spreads your risk.”

6. There are intangibles

“I don't think we understand all that is going on with rotational crops,” says Fredericks. “It enhances soil microbial activity. Soybeans have always been a crop that loosens the soil. Rotations break the plant disease cycle and reduce insect pressure, too.”

More corn diseases come on when you switch to continuous corn, he observes. “You have the resistance issues in insects and weeds. Rotation helps with those, and the soybeans have lower input costs and equipment costs. Soybeans widen the planting and harvest window.”

Fredericks thinks the relative market prices of corn and soybeans may also be shifting back to favor soybeans. “We're in a transitional period of ethanol driving the corn market,” he says. “As that industry matures, I expect soybeans to find a more competitive price position.”

Doubling up

Mark Seib, Poseyville, Indiana, says soybeans give farmers in his area of southwest Indiana a chance to double up on profit opportunities. They double-crop winter wheat and soybeans. The wheat is harvested early in June, then a second crop of soybeans is planted immediately.

The program worked well in 2012; wheat benefited from the spring moisture, then the soybeans responded to rains in the last half of August. “Old-timers say one or the other always makes a crop, and sometimes we get lucky and they both do,” says Seib. “Fertilizer dealers say they've never put on more wheat fertilizer than this year, and that crop will be followed by soybeans.”

Early soybeans also did relatively better than corn in 2012's drought, says Seib. Corn across his farms yielded about one half of normal, just under 100 bushels per acre. Soybean yields were either at or above normal of 60 to 65 bushels an acre.

Seib thinks two other things will give soybeans a boost in acres in 2013. First, getting the corn hybrids he wants may be a problem due to seed shortages of some numbers. Second, continuous corn has depleted soils of nutrients in his area.

“Replacing nutrients is more expensive than ever,” he says.

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