Iron deficiencies seen in Minn. soybeans may cut yields

Corey Hanson, who grows soybeans in Gary in the Red River Valley, has waged many battles against Iron Deficiency Chlorosis, also known as IDC, in his crops.

“It’s always there someplace,” said Hanson. “Just depends on how severe it is, depending on what the spring did, how the [snow] melt happened, and how much rain we’ve received throughout the spring.”

The condition appears when the soybean plants aren’t able to access the iron they need to grow. Affected soybeans’ leaves turn yellow early in their life cycle. When that happens, the plants aren’t actively photosynthesizing, which stunts their development.

Hanson has been trying multiple different treatments over the last 20 years. Lately, he’s been applying liquid iron to his fields, which he says has helped mitigate the severity of IDC. But that increases his costs.

Those cost increases come at a time when many farmers’ operating expenses are already high. Soybean prices are also lower than they were a few years ago. Hanson said that paying for liquid iron to improve yield, in hopes of higher profit, feels like a gamble.

“We don’t know right now what the full price of our soybeans will be next year. We can have an idea, a hope, but we don’t know,” said Hanson. “All my cards to play to get a better yield in hopes of a profit could be all for naught, but I don’t know that now.”

Western and central Minnesota are the areas most affected by IDC. That’s because those zones tend to have soils with poor drainage, weather and soil conditions. That makes it harder for plants’ roots to absorb the nutrients they need for growth and development.

Sergio Cabello Leiva, director of research at the Minnesota Soybean Research & Promotion Council, said that affected plants may mature around harvest time. That’s problematic because farmers want to harvest soybeans when they’re ready and dry.

“When they grow out, they’re gonna be late, probably two, three weeks [behind] the rest of the field,” said Cabello Leiva. “So, when the crop matures, and the farmers go in mid-September, early October to harvest, the other plants are gonna be dry without leaves, ready to harvest. But these [other] acres are gonna be green because they were late.”

Hanson, the farmer, will often find clusters of green soybeans in his fields around harvest time. He says he has to either harvest around them or take them as is. Those soybeans could have higher moisture content, which makes them of lower quality.

“It becomes very much more of a harvesting nightmare, and then the yield is not even close to [ideal] because they’ve been delayed so long,” said Hanson.

Cabello Leiva said there is no silver bullet for Iron Deficiency Chlorosis. So he recommends farmers reach out to an ag specialist for a personalized assessment, as each field is different.