DTN 2020 Digital Yield Tour -- IA, MN, WI

Day 3: Iowa Derecho Impact to Be Determined, But Record Yields Ahead for MN, WI

Darker-green shading shows higher corn yields on Gro Intelligence's real-time yield maps for Iowa, Minnesota and Wisconsin on day three of the DTN 2020 Digital Yield Tour. While Minnesota and Wisconsin are on track for record corn yields, Iowa's crop has several question marks. (Map courtesy of Gro Intelligence)

By Emily Unglesbee

DTN Staff Reporter


Katie Dehlinger

DTN Farm Business Editor

MT. JULIET, Tenn. and ROCKVILLE, Md. (DTN) -- Between drought and derecho, it feels like Iowa's corn crop has been through nine rounds with Mike Tyson. But despite the body blows, the state's corn will likely exit the ring with respectable yields intact, while its northern neighbors -- Minnesota and Wisconsin -- could set records, according to the third day of the DTN/Progressive Farmer 2020 Digital Yield Tour.

Powered by Gro Intelligence, the tour is an in-depth look at how this year's corn and soybean crop is progressing using Gro's real-time yield maps, which are generated with satellite imagery, rainfall data, temperature maps and other public data.

On Wednesday, Gro's models for corn showed a statewide average of 197.6 bushels per acre (bpa) in Iowa, while USDA, which released its first state yield estimates at 11 a.m. CDT Wednesday, estimated Iowa corn yield at 202 bpa. Neither estimate reflects the impact of Monday's derecho.

Gro's estimates for Minnesota and Wisconsin corn at 199.8 bpa and 186.3 bpa, respectively, would set records. USDA anticipates yields of 197 bpa in Minnesota and 181 bpa in Wisconsin.

Soybean yield models for the three states also suggest record or near record yields. Gro forecasts Iowa's soybean yields at a record 60.6 bpa, Minnesota at a record 52.1 bpa and Wisconsin just shy of a record at 54.8 bpa. USDA pegged those state yields at 58 bpa, 51 bpa and 54 bpa, respectively.

You can explore the state yield charts below, keeping in mind that Gro yield models update daily, so numbers may vary slightly from those found in this article:

Iowa: https://app.gro-intelligence.com/…

Minnesota: https://app.gro-intelligence.com/…

Wisconsin: https://app.gro-intelligence.com/…

You can also create a free Gro account for daily updates to yield forecasts and real-time crop health monitoring across the U.S. here: https://app.gro-intelligence.com/….

"It is looking obvious on day three of the DTN/Progressive Farm Digital Yield Tour that U.S. crops are doing very well in 2020 and could be on their way to record corn and soybean harvests," DTN Lead Analyst Todd Hultman said. "Monday's severe windstorm across the central Midwest remains a concern and is waiting a better assessment, but it seems unlikely to detract from the widespread reports of good crop prospects. Thanks to good weather and good crop conditions, corn and soybean prices are likely to remain under bearish pressure heading into harvest."


Gro Intelligence's Vice President of Agribusiness James Heneghan said it will take time for the crop damage from Monday's derecho to be reflected in NDVI maps, which illustrate the greenness of the crop compared to the last 10 years and are a key input to the yield models. However, Gro did calculate the amount of the crop that was put at risk in Monday's storm.

Gro estimates that 7.7 million acres of corn and nearly 6 million acres of soybeans in Iowa were in the path of the storm. Using DTN Weather data, which charted the path of highest winds, Gro compared that path to expected USDA corn and soybean acreage numbers in the area affected. Using Gro's yield figures, that puts about 1.47 billion bushels (bb) of corn and 359 million bushels (mb) of soybean production at risk. The counties of Marshall, Linn, Jasper, Tama and Hardin were among the most heavily hit by the storm, based on average wind speeds that ranged from 77 miles per hour (mph) to more than 92 mph.

Jesup, Iowa, farmer Ben Reinsche said the derecho added a lot of variables to the yield equation.

"It's not a simple exercise of counting kernels and ears and coming up with a standard yield estimate like in the past," he said. "There's a lot of corn that's just defoliated in Linn County. If you have hail fall with a 20-mph wind, how does that differ from raindrops hitting with 100 mph winds? This corn was laid over. Some was broken, some was greensnapped, some was stripped -- it was a tassel, a stalk and an ear. How does that fill?"

Reinsche said corn has about 50 days for grain fill after tasseling, so in 200 bpa corn, that equates to 4 to 5 bushels of fill per day. Farmers often expand that window with fungicide applications. "So, now, if the corn doesn't have leaves to photosynthesize, what's it making a day? Is it making 2 bushels? Is it making 1 bushel? How does defoliated corn finish?"

In his part of eastern Iowa, it's thrown a big question mark over the crop's potential in a growing season that's been excellent otherwise. The crop was planted in a timely manner and in great conditions. "We're actually 10 inches behind on rain for the year, but it came in a beneficial way at my farm so that we really were maximizing conditions through mid-July," he said.

Then it got dry, and Reinsche said his crops in Blackhawk, Buchanan and northern Benton Counties were likely saved by the rain. "We're probably back up to full potential, probably the best crop we've ever raised. That is how we are on Highway 20 close to Waterloo, Iowa. There will be spots that have been dinged by wind or hail, but nothing bad. The wildcard now is in the derecho path."

Gro estimates corn yield averages in those counties at 181.4 bpa, 194.4 bpa and 193.5 bpa, respectively. Jasper County just east of Des Moines boasts the highest county yield average for the state at 209.8 bpa.

Guthrie County, which is just to the west of the state capitol, has the lowest estimate for the state at 175.2 bpa. You can see Iowa's county yield maps here: https://app.gro-intelligence.com/…

Reinsche said he made two trips to western Iowa in the past week, where the corn showed clear signs of drought trouble. Jefferson, Iowa, which is in Greene County, looked as bad as it did during 2012's drought.

Gro's NDVI map for Iowa shows the largest concentration of brown, which indicates less than average crop lushness, just north of Interstate 80 west of Des Moines. Much of the northwestern third of the state shows average to below average crop conditions. You can see Iowa's NDVI map here: https://app.gro-intelligence.com/…

"We definitely see the impact of dryness and flash drought development in Iowa, particularly on corn yield projections," DTN Senior Ag Meteorologist Bryce Anderson said. Flash drought is defined as a two-category degradation in conditions in a 4-week period on the U.S. Drought Monitor. "The impact on corn yield potential is notable due to stress during pollination. Along with the drier trend, July was warm with temperatures from one to three degrees above normal. This added to drying out of moisture from crops and soils," Anderson added.

On a visit to northwestern Iowa, Minnesota farmer and ag consultant Mark Nowak found good-looking cornfields holding some disappointing secrets. The ears he pulled from fields in Cherokee County averaged only 34 kernels in length -- much smaller than the 40-kernel ears he is pulling in his own southern Minnesota fields. "It makes you wonder what exactly is in the ears in those fields," he said of Iowa's droughty spots.

"Recent rainfall will be useful for soybeans across the state along with adding to corn kernel weight in the non-drought areas, but it's too late for corn in the drought-affected sections," Anderson said.

Reinsche agrees, adding that soybeans' short stature helped them weather the windstorm. "Good things come in small packages. There is damage, but since there wasn't hail, and even where there was defoliation, beans can take pretty substantial defoliation and still stay up."

Gro's statewide average soybean estimate of 60.6 bpa would set a new record, and that's reflected on Iowa's county yield maps. The western and north-central portions of the state have yield estimates ranging from 60 to 65 bpa in Sioux County. Clarke County, with an average estimate of 50.7 bpa, is the lowest forecast in the state.


Gro's estimate of a record average corn yield of 199.8 bpa for Minnesota is a bit above USDA's August Crop Production estimate of 197 bpa. It's also well above the 2019 crop, which Gro pegged at 183 bpa and USDA at 173 bpa.

Weather was a key cooperator this year, DTN's Anderson noted. Minnesota hit a record planting pace to start the season. "The drier spring made a big difference in planting rates. By late May, Minnesota corn planting was 98% finished in 2020 compared with just 63% in 2019," he said. The state also caught valuable rainfall systems that skirted Iowa.

"So far, if you had to write a prescription for big crops, this year would have been perfect," added Nowak.

As might be expected, Minnesota's most productive farmland in the southern half of the state shines in Gro's corn yield models. But this year, counties with average yield estimates of 200 bpa and above are far more numerous than previous years, filling the entire bottom third of the state, from the Iowa state line up to U.S. Route 212. Top yield honors go to Waseca County with a yield estimate of 215.4 bpa. As you move north of St. Cloud, yields slip lower, ranging mostly from 140 bpa to 180 bpa. The lowest yielding county is expected to be Beltrami with an estimated average of 127 bpa.

For Nowak, who farms in the southernmost county of Faribault, a record corn crop is not a surprise. "I have observed that the crop looks very good and very consistent where I've traveled in Minnesota, and on my farm," he said. The ears of his cornfields are averaging 40 kernels in length, which is above average and bursting with potential. But weather needs to continue to cooperate. "The early-maturing fields are filled out nicely," he said. "But if we don't get a rain soon, we could get some tipback on the later ones."

Gro's models put the average statewide soybean yield at 52.1 bpa, yet another state record in the making, and slightly above USDA's August estimate of 51 bpa. Last year, Gro pegged Minnesota's soybean yield at 46 bpa, compared to USDA's final estimate of 44 bpa.

As with corn, the state benefited from a rapid soybean planting pace -- 88% done by late May. The lower third of Minnesota counties have the best soybeans, according to Gro's models. From Willmar south to the Iowa border, most yields fall between 55 bpa and 60 bpa, with the far southwestern county of Rock scoring the top yield estimate of 62.3 bpa. In the central tier of counties, Gro's models show more variable yields falling mostly between 35 and 55 bpa. In the northernmost counties, yields hover in the 30s, with the lowest yield estimate falling in Roseau County at 34.8 bpa.

Again, the rest of the month's rainfall will be key, Nowak added. "The beans look great," he said. "But I just checked them and the pods are flat -- we will need a rain soon to fill them, or they will slip a little."


Like Minnesota, Wisconsin growers benefited from the distinctly drier start to 2020. By the end of May, 90% of corn and 79% of soybeans were planted -- miles ahead of the soggy 2019 planting pace.

"That robust start set the stage for high yield potential," Anderson said. "Conditions have remained favorable during the growing season, with Wisconsin in the storm track for follow-up moisture. And, as corn moved into pollination and soybeans into the flower phase, July rainfall totaled mostly from 3 to 7 inches in Wisconsin's primary crop areas. This moisture greatly helped offset any potential crop stress that may have developed from temperatures which were 2 to 4 degrees Fahrenheit above normal."

See Gro's NDVI map of Wisconsin and Minnesota, which measures the lushness or dryness of a region compared to the 10-year average, here: https://app.gro-intelligence.com/….

At 186.3 bpa, Wisconsin's predicted average state corn yield would surpass both a 2016 record and USDA's August estimate of 181 bpa. Last year, Gro also pegged Wisconsin's final corn yield, at 173 bpa, higher than USDA, which came in at 166 bpa.

The state's best corn yields are concentrated in the southern third of the state with another good pocket clustered along the Minnesota border south and east of Minneapolis. In those regions, yields mostly fall between 180 and 200 bpa, with Lafayette County boasting a top yield of 208 bpa. In central and northern Wisconsin, yields range mostly from 155 to 175 bpa, with the lowest yield coming from Sawyer County at 148 bpa.

For soybeans, Gro's models suggest a Wisconsin statewide average of 54.8 bpa, just below the state's 2016 record of 55 bpa, and in line with USDA's August estimate of 54 bpa. Last year, Gro and USDA also agreed on their estimates for Wisconsin's average soybean yield, which settled near 47 bpa.

The southern third of the state boasts the best soybean yields this year, with most estimates there falling between 55 and 60 bpa. The far southern county of Lafayette once again nets the high-yield award, with a Gro estimate of 63.5 bpa. Yields are more variable in the upper two-thirds of the state, ranging from the 50s in the middle of the state into the 40s as you move farther north, with Bayfield County dropping to 40.82 bpa.


Now in its third year, the DTN/Progressive Farmer 2020 Digital Yield Tour, powered by Gro Intelligence, takes place Aug. 10-14 and provides an in-depth look at how the year's corn and soybean crops are progressing. Each day, we'll feature crop condition and yield information from various states, which include links to the Gro yield prediction maps for those states. Yield summaries are viewable at the county level.

The 2020 tour is sponsored by Claas.

The tour started in the west with the first day's articles focusing on Nebraska and South Dakota. On Tuesday, Aug. 11, the tour checked on crop conditions in Missouri and Kansas. On Aug. 12, the tour explored yield estimates from Minnesota, Wisconsin and Iowa. On Aug. 13, we will move into the Eastern Corn Belt -- Illinois, Indiana and Ohio -- before publishing a final look at Gro's overall national yield predictions for the 2020 corn and soybean crops on Aug. 14. Readers should note that the Gro yield visuals are continually updated, while the DTN feature articles are based on the company's yield estimate at the time the article was written. Numbers quoted in the articles may be different than those on the Gro website depending on when viewed.

To see all the tour articles and related DTN stories about the 2020 crop, visit our tour site at: https://spotlights.dtnpf.com/….

About Gro Intelligence: The New York-based company is focused on creating data analytics for the agriculture industry. Gro builds proprietary crop models that use satellite imagery, soil conditions, weather and other crop and environmental data to produce crop health and yield prediction numbers and visuals. In addition to Gro and USDA yield forecasts, the Gro platform provides a one-stop solution for assessing growing and market conditions leading up to this year's harvest.

To learn more about Gro, go here: https://gro-intelligence.com/….

To learn more about their corn modeling system, go here: https://gro-intelligence.com/…. For more on their soybean modeling system, go here: https://gro-intelligence.com/….

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

Follow her on Twitter @KatieD_DTN

Emily Unglesbee can be reached at Emily.unglesbee@dtn.com

Follow her on Twitter @Emily_Unglesbee