Production Blog

Crop Touring From a Distance

Pamela Smith
By  Pamela Smith , Crops Technology Editor
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Variability still exists even in the best of years. Sample pulled from Macon County, Illinois, shows some pollination issues. (DTN photo by Pamela Smith)

DECATUR, Ill. (DTN) -- Call me old-school, but I can't shake the need for dirty-boots learning. For me, a highlight of August is pulling real yield checks to see what we've been cooking in the field all summer.

So, when DTN moved to a virtual format for a yield tour three years ago, I was both curious and contrite. Could satellite imagery, data and modeling replace gathering ears, counting pods and lick-the-lead-pencil math?

Each year, I've continued to trek to the field to do a bit of ground truthing. This year my efforts were somewhat hampered by COVID-19 and being socially distanced from my grains analyst son, who is an especially good traveling partner when there are numbers to be crunched.

The cool thing about the DTN/Progressive Farmer 2020 Digital Yield Tour, powered by Gro Intelligence, is that the yield maps can cover a lot more territory than I can tromping through fields. They are also continually updating.

We all know any type of yield sampling is a snapshot in time. Last week, Gro's forecast showed the potential of a national average corn yield of 183.9 bushels per acre (bpa) and a soybean yield of 53.1 bpa. The corn yield estimate is 2.1 bpa higher than USDA's August estimate and 0.2 bpa below USDA. Neither estimate accounts for the damage from the derecho that smacked Iowa's crop with hurricane-force winds.

We also know how much variability there can be within a county and let's be honest, within a field. I found it when I randomly selected a field in Macon County, Illinois. The most recent Gro Intelligence estimate for Macon County pegged the corn crop average at 206.8 bpa and soybeans at 63.70 bpa.

I instantly knew the corn field I'd checked had problems when I entered. Plant health was pretty good, but more than a few stalks had fallen or tipped willy-nilly at the soil surface. Brace roots looked as though they'd made an effort to reconnect to right the plant. My guess -- wind injury. There were also pollination issues. I measured the crop at 129 bpa. Oof.

I'm pretty sure the yield monitor will uncover some better yields in that same field this fall.

The adjacent soybean field though, was like ... wow. I counted 1,577.53 pods in a 3-by-3-foot square. Conversions of pod counts to yield have always been tricky since soybeans are like cats -- you never know what they are going to do next. Still, I found lots of four-bean pods and they were filling out nicely top to bottom.

When I pull three random soybean plants as the quick sampling methods dictate, I often wonder if my hand doesn't inadvertently twitch toward larger stems. However, the consistency I found in this field was remarkable. Noticeably missing were those fried looking flowers we often see this time of year and every stem had multiple nodes and branches.

The field contained a wee bit of waterhemp, but unless a herd of buffalo or gobbling grasshoppers show up, the combine should find a bunch of beans in that field.

About 20 miles west (again in Macon County), I measured a 217 bpa corn yield, but still found some ear size variability and pollination issues. Ear placement also varied a bit, which goes along with that cold, wet start we got this spring in this area.

Scott Wallis, a Princeton, Indiana, farmer who we followed throughout the season last year as part of DTN's View From the Cab series, was an industrious scouter for me this year. He purposefully retrieved a range of samples in Gibson County, Indiana, of his dryland crop -- all planted in 20-inch rows.

The Gro estimate of 188.1 bpa for would be just slightly less than the 192 bpa record for Gibson County, Wallis noted.

In what Wallis considers his best field (planted April 7), he pulled a 250.9 bpa estimate last week. A middle-of-the-anticipated yield field (planted April 9), came in at 239.2 bpa. And a field containing lighter soil types (planted April 15) was estimated at 222.3 bpa.

"That would be a record yield on that lighter soiled ground by 10 to 15 bpa," Wallis said. "Our hilly, lighter soils may not out-yield our best soils this year, but I believe the percent increase we experience in yield will be more."

In fact, the darker soils may be suffering from a bit too much water of late, he noted. "That ground has been moist to sticky for the past 45 days. We're starting to see some evidence that those fields are wanting for nitrogen -- not because they ran out as much as they can't access it from being too wet," Wallis said. He experienced 7 inches of rain in July.

Corn is about 25% milk line and pollinated to the tip. A little leaf disease was showing up as fungicide lifespan was coming to a close, but nothing that would compromise yield, Wallis figured. Stand counts indicate consistent germination across all soil types.

For soybeans, Wallis pulled samples from what he considered his best field, planted April 3 and currently at R-6 growth stage. His yield check sample average found 96 pods and 21 plants in a 3-by-3 square on 20-inch rows. Whoa ...

Three miles away sits a field planted April 22 that he considered tearing up when cold, wet conditions hampered germination and growth. He dropped about 130,000 population and ended up with 80,000. But his yield sampling this week still found 18 plants in the 3-by-3-foot sample averaging 70 pods per plant.

"I've never seen this many nodes and pods on soybeans. They are loaded up," Wallis said.

Water in the right amounts is key and even irrigation isn't always enough to keep corn from stressing, noted Quentin Connealy. The Tekamah, Nebraska, farmer, who also serves as one of DTN's brand ambassadors, pulled a 208.1 bpa test sample from his field in Burt County. The Gro models are currently showing his county at 206.7 bpa. Reminder -- those figures change daily.

Connealy said his area receive 1.5 inches of rain in July and has received just 0.55 inch in August.

In central Nebraska, Ethan Zoerb, another of DTN's brand ambassadors, thinks Gro's estimate of 190.7 bpa for Custer County is low if he uses his crop as comparison. His own corn yield sample estimated 204 bpa, and came up shy of the 250-275 bpa he expects that field to make.

"We have some wind damage that will take the top end yield out of some of our crop," Zoerb said. "But we have irrigated acres that will come close to 300 bpa."

There's no question that new technology gives us some interesting insights into the crop, even if it comes from a distance. And, there's a lot to be said for losing the itch factor that comes with scouting fields this time of year.

Ultimately, the yield monitors will tell the tale. Still, I did learn one valuable thing while scouting this year. Those neck gaiters that are so controversial as COVID cover-ups are darn good for dodging facial corn cuts.

Find an easy formula for figuring yield here:…

Here's a summary of our virtual yield tour's state findings, using Gro Intelligence's yield estimates from our published stories. Because Gro Intelligence's yield models update every day, the numbers on their website may differ from what you see below.

You can find detailed articles on each state at:…





The DTN/Progressive Farmer 2020 Digital Yield Tour, powered by Gro Intelligence, provided an in-depth look at how the year's corn and soybean crops were progressing during the week of Aug. 10, 2020. It featured crop condition and yield information from various states and included links to the Gro Intelligence yield prediction maps for those states, which included county level yield summaries.

CLAAS sponsored the 2020 digital yield tour.

The "tour" started in the west, with the first day's articles focusing on Nebraska and South Dakota. On Aug. 11, the tour examined yields in Kansas and Missouri before moving into Iowa, Minnesota and Wisconsin yields on Aug. 12. The Eastern Corn Belt -- Illinois, Indiana and Ohio -- took center stage on Aug. 13, and national estimates were released on Aug. 14.

New York-based Gro Intelligence is focused on creating data analytics for the agriculture industry. Gro Intelligence 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 Intelligence, go here:….

To read the research white paper on Gro Intelligence's modeling system, go here and select to "Download the corn yield model paper":….

Pamela Smith can be reached at

Follow her on Twitter @PamSmithDTN


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