MOUNT JULIET, Tenn. (DTN) -- Considering the wet spring that plagued Nebraska and South Dakota this year, corn and soybean yields are holding their own, but growers say average yields conceal a wide variation of crop conditions.

The DTN/Progressive Farmer 2019 Digital Yield Tour, powered by Gro Intelligence, 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 Tuesday, all of Gro's estimates for corn and soybeans in South Dakota and Nebraska were lower than USDA's yield estimates from Monday's Crop Production report.

Gro's models for corn show a statewide average of 182 bushels per acre in Nebraska and 149 bpa in South Dakota. USDA pegged those states at 186 bpa and 157 bpa, respectively.

Gro forecasts Nebraska soybean growers will harvest 56 bpa compared to USDA's 58 bpa estimate, while South Dakota farmers will harvest 37 bpa compared to USDA's 45 bpa estimate.

You can see specific comparisons in these charts:

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

South Dakota: https://app.gro-intelligence.com/…

Gro's yield estimates on a county and state level update on a daily basis, so the numbers at publication time may be slightly different than what you find on the Gro website.

DTN Senior Ag Meteorologist Bryce Anderson said the growing season in both states got off to a difficult start. In South Dakota, it was the ninth coldest season on record and the fourth wettest in 125 years of record keeping.

"The state's producers have been stymied by this calamitous start to the season. Estimates of corn prevented planted acreage show South Dakota with more than 2.8 million acres that were left unplanted because of the cold-and-wet pattern, and associated flooding," he said.

In Nebraska, the storms have lined up one after another, and all but the southwestern corner of the state has had above-normal, and in some cases significantly above-normal, precipitation. As a result, the crop is highly variable, with some areas benefiting from cool temperatures and ample moisture and others suffering from the same conditions.

NEBRASKA

Gro Intelligence's yield maps show average corn yields ranging from a low of 118 bpa in Grant County to a high of 211 bpa in Hamilton County. Those two counties have very different growing conditions, with Grant County located in the more arid western part of the state and Hamilton County in the land of center pivot irrigation. You can see the county level map of Nebraska here: https://app.gro-intelligence.com/….

With a statewide average of 181 bpa, Nebraska has one of the highest average yields of the 10 states included in DTN's Digital Yield Tour, and it's only 11 bpa shy of last year's bin-busting 192 bpa.

Gro's yield estimates incorporate another set of maps, known as the normalized difference vegetation index (NDVI), which use satellite imagery to show how abnormally dry or lush an area is, using a 10-year average "greenness" index. Those maps show areas that suffered from the excessively wet spring, but much of the damage tracks along the Platte River and Missouri River valleys.

You can find that map here: https://app.gro-intelligence.com/….

"It's impressive how the eastern one-third of the state has a vegetation index that is either average to below, with many indications of prevented planting," Anderson said. "In southern Nebraska, it appears that we are seeing the impact of extremely heavy rain in July that caused extensive flooding. Central Nebraska shows the effect of a lot of rain in midsummer, with the NDVI value indicating above-normal vegetation conditions."

Randy Uhrmacher farms in Adams and Webster counties in south-central Nebraska, where Gro forecasts corn yields of 199 bpa and 165 bpa, respectively.

"Those seem about right considering the storm damage," he said, adding that Adams County is primarily irrigated ground while Webster is mostly dryland. There are also more drowned-out spots and areas of poor germination in Webster County this year.

Uhrmacher said this spring's storms were spotty, and it seemed like he always had a dry field somewhere to plant, so while he wrapped up corn planting in late April and soybean planting in mid-May, there were farmers that planted up until around June 10.

Gro pegs the average Nebraska soybean yield at 56 bpa, 3 bushels below NASS' final estimate last year. Yields range from a low of 39 bpa in Hooker County to a high of 69 bpa in Phelps County.

Uhrmacher said the early planted soybeans are podded well, and he's happy with how they look. He hopes that some of his irrigated soybeans will yield 80 bpa.

But he adds that late-planted soybeans are struggling.

"There are probably more train wrecks out there than normal," he said. "The good stuff is there, but it didn't take much to mess it up."

SOUTH DAKOTA

Gro Intelligence forecasts South Dakota corn yields will be lower than last year at 149 bpa. Gro's final yield estimate for South Dakota last year, at 153 bpa, was lower than USDA's, at 160 bpa.

Like Nebraska, the range of county yields is wide, but that also reflects different soils and growing conditions in the state. The highest corn yield estimate is 172 bpa in Union County in the state's far southeastern corner while the lowest estimate is 59 bpa in Shannon County in the state's southwest. You can view county level yields here: https://app.gro-intelligence.com/….

South Dakota led the country in prevented planting acreage this year with a total of 3.86 million acres, 2.8 million of which were corn and 850,000 of which were soybeans. Those acres show up strongly in GRO's NDVI map, with a heavy concentration in the southeastern corner of the state.

Tregg Cronin, who farms in Potter County, said fall crops in his region look outstanding given the tough start to the growing season. He disputes Gro's forecast of 101 bpa for his county, adding that he thinks 90% of the fields will yield more than that.

His farm usually stretches corn planting over a comparatively wide window. So his earliest-planted corn went in 10 days to two weeks behind normal, while his latest-planted corn was only five to six days late.

They decided to stop planting corn on May 31. They still had soybean and sunflower seeding left to complete, and chose to only have two late-planted crops rather than three.

"Believe it or not, our earliest corn is not light years ahead," he said. Soil temperatures were on the lower side and the corn took a while longer to germinate than later-planted corn. Then July temperatures were lower than average, and without a hot-and-dry spell to slow it down, the corn grew quickly.

On Tuesday, Gro's models estimate South Dakota's average soybean yield at 40 bpa, down from last year's 45 bpa. Todd County has the highest average yield at 51 bpa while Pennington has the lowest at 25 bpa.

As with corn, Cronin thinks Gro's models underestimated yield potential by pegging Potter County yields at 34 bpa. He said the beans are bigger and bushier than normal, and he thinks 50 bpa is achievable. And because of the cool, wet weather, they're considering applying fungicide. "We just don't normally get enough moisture to have concerns," he said.

On Wednesday, the digital "tour" will turn its focus to Iowa, Minnesota and Wisconsin. If you'd like your yield observations to be included in future stories, email DTN using the contact information below.

ABOUT THE TOUR

The DTN/Progressive Farmer 2019 Digital Yield Tour, powered by Gro Intelligence, takes place Aug. 13-16 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 "tour" starts in the west, with the first day's articles focusing on Kansas and Missouri and Nebraska and South Dakota. On Aug. 14, the tour will explore yield estimates from Minnesota, Wisconsin and Iowa. On Aug. 15, 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 2019 corn and soybean crops on Aug. 16. 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 2019 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.

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

To read the research white paper on their modeling system, go here and select to "Download the corn yield model paper": https://gro-intelligence.com/….

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

Follow her on Twitter @KatieD_DTN

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