ROCKVILLE, Md. and MT. JULIET, Tenn. (DTN) -- The country's stark divide between the haves and have-nots of rainfall this year was on full display on Day One of the 2021 DTN Digital Yield Tour. Continued drought is dragging corn and soybean yields in the Dakotas down below average, as the well-watered state of Nebraska instead edges toward record corn and soybean crops.
Powered by Gro Intelligence, the DTN Digital Yield Tour is an in-depth look at how this year's corn and soybean crops are progressing using Gro's real-time yield maps, which are generated with satellite imagery, rainfall data, temperature maps and other public data. Unlike static estimates, Gro's yield projections update daily on a county and state level, so the numbers at publication time may be slightly different than what you find on the Gro website.
On Monday, Aug. 9, the Gro models predicted a statewide average of 187.6 bushels per acre (bpa) for Nebraska's corn crop and a 60.3-bpa average soybean yield, both near record highs for the state. In contrast, the models expect South Dakota's corn crop to land closer to 142.7 bpa, down 20 bpa from last year, while its soybean crop is still holding onto average potential, with a current statewide yield estimate of 44.7 bpa.
Although Gro does not yet have a fully developed corn yield model for North Dakota, the company pulled together a "rapid-response" model to capture the drought's effects in that region this summer, said Mintak Joo, senior research analyst for Gro. It suggests North Dakota's corn crop is moving toward a statewide average of 120 bpa, down nearly 20 bpa from last year. The company's soybean model pegs the state's soybean average yield at 33.9 bpa, on par with last year, for now.
To see Gro's yield models and explore the county-level detail for each state, navigate here:
-- Nebraska: https://app.gro-intelligence.com/…
-- South Dakota: https://app.gro-intelligence.com/…
-- North Dakota: https://app.gro-intelligence.com/…
Spring and summer rainfall patterns made all the difference in these states as expected, said DTN Ag Meteorologist John Baranick. While both the Dakotas and Nebraska were facing some level of drought conditions in early March, only Nebraska was able to break away from that trend, as La Nina abruptly abated and allowed several well-timed storm systems to visit the state.
"Several storm systems moved out of the Rockies and through the Central Plains, eliminating drought across Nebraska," Baranick recalled. "But the Dakotas always seemed to be on the outside looking in. Storm after storm missed to the south, and when the occasional storm did move through the region, it was largely unimpressive and did not carry either widespread or heavy rain with it."
The result was a steady decline in crop conditions and projected yields for both North and South Dakota, Gro analysts explained. Keep in mind that the near-average soybean yields currently shown in Gro's models for those droughty Dakota fields are far less settled than corn yield estimates, added Gro's Joo. That's a result of the difference in the biology of soybean plants compared to corn, where yield is established earlier in the season, from pollination onward. "The full weather effect is not happening yet because we're not past the critical period yet for the (soybean) crop," Joo explained.
-- Corn: 187.6 bpa, up 6 bpa from last year.
-- Soybeans: 60.3 bpa, up 3 bpa from last year.
Gro's yield models for Nebraska show the benefits of farmers' access to deep irrigation wells in the central part of the state and sufficient spring rainfall in the eastern third. "We did see some areas of Nebraska where patchy drought crept back into the picture," Baranick noted. "But, in many cases, the drought is occurring where crops are heavily irrigated. And the ample moisture from the spring helped to recharge groundwater to have plenty through the summer."
Gro's NDVI maps, which measure a region's lushness or dryness relative to average conditions, tell the overall picture of a state dealing with average moisture levels as a result. "While there are some pockets in Nebraska where conditions might be suboptimal, most of the state is right around average for this time of the year," Baranick concluded. See the NDVI map here: https://app.gro-intelligence.com/….
The highest estimated corn yields hearken from those irrigation-fed north-central and south-central counties of the state, ranging from the 180s up well into the 200s. Phelps County wins the high-yield estimate for now, with the south-central county showing a current average yield of 225 bpa. Farther west, average yields slip into the 160s and 150s and finally bottom out in the far southwestern county of Kimball, at 130.2 bpa.
For soybeans, which, as Gro's Joo noted, still have yield potential to gain or lose at this time of year, the bottom central third of the state is showing the highest yield averages so far. There, yields range from the upper-50s into the upper 60s, with Hamilton County showing a statewide high yield of 67.6 bpa. Yields are lowest in the Nebraska Panhandle, with the county of Dawes dropping as low as 29 bpa.
-- Corn: 142.7 bpa, down 19.3 bushels from last year.
-- Soybeans: 44.6 bpa, down less than 0.8 bushel from last year.
While South Dakota's statewide average yield is the lowest in the last five years, averages do not tell the whole story. According to Gro's yield model, there's a spread of more than 100 bushels per acre between South Dakota's highest county corn yield and its lowest, if you only look at the main farming region east of the Missouri River.
It's bleaker if you include the drought-ravaged western half, although that area doesn't produce a lot of corn or soybeans.
"In South Dakota, there is a big difference between west and east. There are almost no areas west of the Missouri River that are in good shape, but it's more of a mixed bag east of the River," Baranick said. "That could be due to some more local rainfall and timely rains at that."
As a result, the state's NDVI map looks like a gradient. With tan coloring indicating drought and green coloring indicating healthy crops, the map starts out a deep brown in the western half and transitions to white (average) and darker green in the southeast. See the NDVI map here: https://app.gro-intelligence.com/….
The best yield potential falls along the state's southern and eastern borders, with Gro's models suggesting the highest average corn yield potential exists in Hamlin County, which is to the northwest of Brookings, at 185.5 bpa. The eastern corridor along the Minnesota and Iowa border also reflects strong yield potential, with county averages ranging from 167 to 177 bpa. The lowest average yield east of the Missouri River is 81 bpa in Edmunds County near the North Dakota border.
For soybeans, the highest yield potential is in South Dakota's most southeasterly counties. Union County soybeans are forecast at 55.85 bpa, and counties along the Interstate-29 corridor show mostly 50 bpa or above. The lowest soybean estimate is in northwestern Campbell County at 31.3 bpa. Other counties in the state's north-central regions have yields estimates below 35 bpa.
-- Corn (unofficial yield model): 120 bpa, down 19 bpa from last year.
-- Soybeans: 33.9 bpa, on par with last year.
Gro's Drought Index shows clearly how North Dakota has suffered some of the worst drought conditions in the Northern Great Plains this year. On a scale ranging from 0 to 5, with 5 being the most severe, much of the western, northern and central counties of the state rate from 4 to 4.6. (See the Gro Drought Index here: https://app.gro-intelligence.com/….)
"In North Dakota, the drought has been going on the longest with the least amount of relieving rain than any other state on the tour," explained DTN's Baranick. "There are very few areas that have handled the drought well there. There was a rogue cluster of thunderstorms that produced heavy rainfall in early June across the southeastern corner of the state, but this area has mostly been holding onto that rainfall since."
Gro's unofficial corn yield model unsurprisingly suggests the drought could push the state to its lowest statewide corn yield since 2013, when corn only reached 110 bpa on average. "That whole eastern third of the state, north to south, all corn yields are down significantly year over year, 10 to 20 or more bpa," said Gro Senior Research Analyst William Osnato.
For now, soybean yield potential is hanging on, with the final weeks of pod and seed development ahead of it yet. The eastern third of the state shows the most promise, with yield potential hovering in the low 30s, and the southeastern county of Sargent holding a statewide high of 44.4 bpa. Farther west and southwest, yields tumble into the 20s and teens, with Golden Valley County registering a statewide low of 17.5 bpa.
Tomorrow, Aug. 10, the tour will examine the corn and soybean production potential of Missouri and Kansas. On Wednesday, Aug. 11, the tour will explore Minnesota, Wisconsin and Iowa. On Aug. 13, it moves into the Eastern Corn Belt, specifically Illinois, Indiana and Ohio. And on its final day, Aug. 14, DTN will publish Gro's overall national yield predictions for the 2021 corn and soybean crops.
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