2023 DTN Digital Yield Tour -- SD, MN

South Dakota Corn Yield Estimates Rebound While Minnesota Crops Struggle With Drought

This map shows this year's yield forecasts compared to the rolling five-year average, highlighting areas of higher-than-normal yield potential in green and lower potential in brown. (Map courtesy of Gro Intelligence)

MT. JULIET, Tenn. (DTN) -- South Dakota caught the rebound rains. Most of Minnesota did not.

"South Dakota and Minnesota went in two different directions with the weather," DTN Ag Meteorologist John Baranick said. "Both had issues with early planting due to lingering cold and snowfall early on in the season, but South Dakota did much better on the rainfall situation."

One to 3 inches of rain fell across a wide swath of South Dakota on June 23, turning around a season that appeared headed toward droughty disaster. At one point, Gro Intelligence's corn yield estimate for the state dipped below 135 bushels per acre (bpa).

Now, Gro estimates a statewide yield of 159.4 bpa, 2.6 bushels shy of the record, according to the fifth and final day of the DTN Digital Yield Tour, which is powered by Gro's corn and soybean yield models.

For Minnesota, Gro's 180.8-bpa yield estimate is below the five-year average and a far cry from last year's record 195-bpa yield.

Kelly Goughary, a senior analyst at Gro Intelligence, said Minnesota's corn yield estimate has been steadier throughout the season, and never saw high levels of vegetative health like other rebound states.

"I don't think they've seen the revival rains, and that's directly reflected in the yield," she said.

Soybeans follow a similar pattern to corn. South Dakota's 45.8-bpa estimate is above average, while Minnesota's 47.2-bpa estimate is below.

During the past week, the Digital Yield Tour has been highlighting the haves and have-nots of rainfall using Gro's corn and soybean yield models, which update daily to incorporate new data. Yield projections are generated using satellite imagery, rainfall data, temperature maps and much more beginning at the county level. County yield averages are then used to generate state and national yield estimates.

DTN Lead Analyst Todd Hultman said it's helpful to take a deeper look at each state's experience.

"I think we see a lot of very unique stories state-to-state of what they were dealing with this year. And the fact that we're navigating through a weather situation that we can't really compare easily to any other year is obviously a challenge," he said. "But how nice to have objective data tools like this to get us to kind of face the factual situation."

You can also learn more about Gro Intelligence's yield models by attending the DTN Ag Summit Series virtual event on Aug. 15. Gro analysts will explain more about their model and take questions. You can find more information at www.dtn.com/agsummit.

Details on Minnesota and South Dakota's corn and soybean crops can be found below.

This is the final day of the Digital Yield Tour. Read the rest of the week's stories here:

-- Day 1, National: https://www.dtnpf.com/…

-- Day 2, IL IN OH: https://www.dtnpf.com/…

-- Day 3, NE IA WI: https://www.dtnpf.com/…

-- Day 4, KS MO: https://www.dtnpf.com/…

For your convenience, all the stories, videos and images from the tour can be found at https://spotlights.dtnpf.com/….


Corn: 159.4 bpa

-- USDA five-year average: 146.4 bpa

-- High: Moody County, 191 bpa

-- Low: Haakon County, 80.7 bpa

Soybeans: 45.8 bpa

-- USDA five-year average: 42.3 bpa

-- High: Moody County, 56.2 bpa

-- Low: Meade County, 25.6 bpa

Weather Comments: "South Dakota had an early dry stretch like most of the Corn Belt, but the recovery was quicker," Baranick said. "A solid storm system brought widespread 1 to 3 inches across most of the state on June 23. It also came with some severe weather, but the rainfall since has been pretty good too," he said.

If the western half of the state planted corn or soybeans, it would have had nearly ideal conditions. "But, alas, most of that occurs east of the Missouri River. Still, the eastern side of the state also had some pretty good rainfall overall, and more timely and frequently than Minnesota. Though still in partial drought in the U.S. Drought Monitor, I'm not surprised to see solid yields coming out of that state," Baranick said.

Gro Comments: The big factor driving the turnaround in South Dakota's corn yield estimate was the normalized vegetative differential index, more commonly referred to as the NDVI. The index measures the color of the crop to gauge its photosynthetic activity and health compared to average.

"We saw record-high NDVI in mid-July in South Dakota," Goughary said. The state's southeastern counties saw many average county corn yields above 180 bpa. The northeast corn looked strong, too, and the soybeans there, especially, could benefit from recent rains.

Soybeans are in a very similar situation to corn with a strong NDVI paired with significant drought recovery.

Farmer Comments: Winter precipitation helped recharge the soil profile in southeast South Dakota where Kevin Scott and his family farm in Minnehaha County near Valley Springs.

"Our soil profile starting the season was excellent," he said. "Our tiles were running and planting conditions were good. We planted on time or maybe a little better."

Throughout the spring and into the beginning of summer, only light showers totaling four- to six-tenths inch at a time fell across the area. Scott said that meant the corn and soybeans sent their roots down searching for subsoil moisture, and all in all, stands remained looking excellent. The corn pollinated well, and soybeans canopied their 20-inch rows. However, as the calendar turned to July, the rains stopped.

"Our crop held on really quite well into July and didn't show much stress until the latter part of the month. Then, things started going backward," Scott said. "We had about a two-week period where there was some damage done, and we were losing some bushels. There are places in the cornfields that are burned up, but not too terrible bad in our area."

One emerging issue that Scott dealt with this year was soybean gall midge, a pest whose larvae feed on tissue in soybean stems. Damage is often concentrated on field edges.

"Some of my edges are 65% to 85% gone, maybe 30 to 40 feet into the field," he said. "We're trying to figure out why it's happening and try to mitigate that in the future."

Rains returned as August began, which paused the backslide in yield potential. Field scouting didn't reveal much tip back on corn ears, and Scott said he believed his crop had potential to fill the ears that are present. His soybeans weren't quite chest high yet, but he felt they might finish that way. However, the prognosis for crops on lighter, sandier soils in the region isn't as positive.

"I talk to my agronomist regularly, and he said there are some areas that will not recover even with the moisture we just had. They've just been hammered," he said. "Overall, we're going to be down a little bit in this area as compared to last year, even if we get more rain."

Scott said that overall, his farm should hit average production history yields, numbers that have risen significantly in the past few years.

"I guess you'd say it's a typical year of farming," he said. "I've farmed 42 years, and I never say it's a normal year because I don't know what 'normal' is."


Corn: 180.8 bpa

-- USDA five-year average: 183.6 bpa

-- High: Martin County, 204.1 bpa

-- Low: Carlton County, 113.7 bpa

Soybeans: 47.2 bpa

-- USDA five-year average: 48 bpa

-- High: Martin County, 59.5 bpa

-- Low: Saint Louis County, 32.72 bpa

Weather Comments: "Out of all the states in the tour, Minnesota had the lowest rainfall over the past 90 days, though Wisconsin was probably just as bad," Baranick said. Some areas got some decent rain, though it largely came in big chunks rather than being spread out throughout the season. It also may not have been as timely.

"The southwestern corner fared better, and the drought situation there was not as severe, but the rest of the state didn't do as well. We saw widespread rains return to most of the Corn Belt, but Minnesota seemed to be on the losing end of most of that rainfall," he said.

"There's a fairly solid stripe on Gro's models from the Red River Valley to the southeast corner where the rains have missed, drought increased, and yields are largely below their five-year average. And those counties in the southeast are some of the most productive fields in the state. It's been a true disappointment," Baranick said.

Gro Comments: Minnesota is one of the only states on this year's Digital Yield Tour that the average yield has trended lower during the past 30 days. Minnesota never saw the type of rebound experienced in South Dakota, Iowa and Illinois, and Goughary said the yield model has been more consistent throughout the year.

"It didn't really hit a low, and it's just been kind of poor all season," she said.

The state's highest yields are in the southwest, where it caught some of South Dakota's rainfall. While they're good compared to others, that region is still expecting yields that are below average.

As for soybeans, Gro's yield estimate matches the lowest forecast of the season.

Farmer Comments: After enduring an extremely dry fall in south-central Minnesota last year, Mark Nowak said his subsoil moisture in Faribault County was pretty much exhausted as 2022 came to a close. However, winter brought with it a pattern of rain and slushy snow.

"We had a lot of precipitation, but we didn't have a lot of frost, so it all soaked in," said Nowak, who farms near Wells, about 15 miles north of the Iowa border. "I was thrilled this spring when the thaw came. My tile outlets were flowing."

April was drier than average, he commented, with about 60% of normal rainfall. When he began planting corn on May 2, he described the conditions as the absolute ideal planting scenario.

"We had moisture on top, and we knew we had moisture down below," he said. "We were feeling really good about the corn going in."

Soybean planting began May 7, and Nowak got in about a third of his bean acres before rains started on May 10. Over the course of five days, his fields received anywhere from 5 to 7 inches of rain. As it dried, what had been mellow, workable ground was now compacted and crusted.

"I saw something this year I have never seen before," Nowak said, noting that it was his 50th season. "That crust was so difficult. The beans were just bound and determined to push through. As they emerged through the crust, it would rip off the cotyledons. You'd go out there and just see stems."

Replanting wrapped up by the beginning of June, which again was a drier-than-normal month, but Nowak said a handful of timely showers kept his crops rolling forward. A few more rains fell in the middle of July, but starting July 16, the farm didn't receive another drop of rain for 21 straight days. Fortunately, the dry spell wasn't accompanied by extreme heat.

"We've had only one day in this area where the temperatures touched 90 degrees, so that really helped to not stress that crop," he added.

Stabilizing rains returned the first weekend of August. His corn was showing a little tip back, but no more than normal.

"If you don't have a little tip back, you're probably not planting enough population," Nowak said. "I've always said the perfect corn ear is 16 rows around, 40 kernels long and a stand of 34,000. That about where we're at today, but will we get enough moisture to fill out that potential? I'm saying we need 2, maybe 3 inches of rain to really put the finishing touches on this crop."

After the dry conditions in June caused some iron deficiency chlorosis in his soybeans, Nowak said the crop grew out of it and is looking pretty good.

"They're growing and putting on blossoms. They'll put on pods, but it's way too early to even begin to think about what it could amount to," he said. "They look like they've got a lot of potential, but that potential is still evolving.

"I'm a little bit optimistic that we've got a pretty good crop coming here," he said. "Maybe not the best crop ever, but at least a good crop."

-- Watch the corn grow! DTN, in partnership with Farmers' Independent Research in Seed Technology, have placed a camera in eight FIRST test plots, adding a new image to the video each day. This one is in New Richland, Minnesota. Watch it here: https://www.dtnpf.com/…

Katie Dehlinger can be reached at katie.dehlinger@dtn.com

Follow her on X, formerly known as Twitter, @KatieD_DTN