Harry Stine’s Accidental Discovery May Revolutionize Farming
Dirty dishes left by Alexander Fleming spawned the Scottish biologist’s accidental discovery of penicillin. All John Pemberton wanted to do was cure headaches when he invented Coca Cola by mixing coca leaves with cola nuts. Then there’s Harry Stine.
The founder of the Stine Seed Company couldn’t find the labor to hand-thin his company’s corn test plots – a then-common practice in the 1970s. Forty years later, this accidental step, just like the others, is poised to revolutionize an industry.
Stratospheric Seeding Rates
Stine Seed Company in Adel, Iowa, is planting corn in stratospheric corn populations in increments from 45,000 to 60,000 plants per acre – roughly a 25% to 50% hike above current populations – and in a more equidistant manner in a system called twin-row 20-inch spacings.
Just by themselves, Stine tests show the more equidistant spacing raises yields an average 3% to 9%. That’s just the start, though. Matching the right high-population hybrid with the right field could pick up another 5% to 12% in yields.
Meanwhile, proper fertility, including regularly scheduled N applications, can boost yields another 10% to 20%.
“This is really taking an agronomic system to the next plateau,” says Jerry Hatfield, director of the USDA’s National Laboratory for Agriculture and the Environment in Ames, Iowa.
How It Started
This strategy coincides with data Stine reviewed by the late Don Duvick, the legendary Pioneer Hi-Bred (DuPont Pioneer’s precursor) corn breeder. Duvick’s data showed that high yields coincided with higher corn populations.
On a per-plant basis, ear size of .33 pounds has not changed from the 1930s to 2016. What has caused yields to quadruple in this time period is plant population. It’s also increased fourfold.
“What’s changed is the ability of modern corn plants to withstand levels of density stress,” says Stine.
“Yield levels have risen exactly in correlation with the increase in population. So to get higher yields in the future, we will need high populations,” Stine says.
“We pat ourselves on the back by raising (U.S.) corn yields 1½ bushels annually,” says Hatfield. “Long term, though, that yield increase will come 50 bushels per acre short of what it will take to feed the world by 2050.”
All this starts with Stine’s 1970 plot work.
“It’s embarrassing, really,” says Stine. “We didn’t understand what we were doing at the time. We started out planting higher populations, not because we knew something, but because we didn’t have the manpower to overplant and thin.”
This practice, which was standard at the time, ensured picture-perfect picket-fence stands straight out of a seed corn commercial.
It took much manpower, though. Stine figured labor could be better used planting more hybrids. Additional stress keyed by thicker planting also meant hybrids with stalk problems and poor standability would be automatically screened out. The surviving hybrids formed the forerunners of the firm’s specially designed hybrids that thrive at ultra-high populations.
These 6- to 8-foot-tall plants look different from today’s typical 9- to 11-foot-high hybrids. More upright leaves and smaller tassels enable plants to harvest more sunlight, says Hatfield.
Plants planted this thick, though, wouldn’t work in conventional 30-inch rows. Plants would be squished too close together. The more equidistant spacing that results from the twin-row 20s reduces plant crowding.
Initially, Stine planted the hybrids in 12-inch rows, but existing combine heads didn’t work well. This was overcome by planting 8-inch twin-row spacings separated from the next twin row by 12 inches.
Harvest isn’t a hassle if you have a 20-inch corn head at harvest, says Stine. “With a 20-inch-row corn head, you can go any direction you want,” he says. “You could go sideways if you wanted to.”
Yields Don’t Always Rise
Higher yields don’t always result, though. In Jim Fuchtman’s case, irrigated 30-inch-row corn yielded 239 bushels per acre in 2015, compared with 208 bushels per acre in 20-inch twin-rows.
“It was my lowest-yielding corn,” says the Creighton, Nebraska, farmer.
There’s a catch, however. He mainly planted 110- to 112-day hybrids in 30-inch rows, where a 107-day relative maturity corn was planted in the twin-row 20 field.
“It did not matter what the hybrid was, it’s just that long-season corn was better for 2015.”
In 2014, a year with low heat units, Fuchtman’s 107-day corn outyielded later-maturing hybrids.
“I haven’t given up,” says Fuchtman. “I believe in the concept, but they don’t have the right hybrids for it yet.”
Here's what Fuchtman had to say about high population corn:
In other cases, twin-row 20s went gangbusters in 2015. Jason Moellers’ yield of 265 bushels per acre in his twin-20s edged 30-inch-row yields of 220 bushels – an eye-popping 45-bushel-per-acre difference.
The West Union, Iowa, farmer found there was more expense, though. More plants need more food. He complements commercial N application with manure.
He normally applies a stabilizer with N and then adds 50 to 80 pounds per acre more than normal. “The ultimate goal is to spoon-feed N and then fly on some encapsulated urea at tasseling,” he says.
Fungicides also are key. The intensive plant populations and accompanying residue form a disease haven.
Will Farmers Switch?
There’s a major stumbling block. Equipment conversion costs tally in the hundreds of thousands of dollars. Costs for a new planter and larger combine to run a 20-inch head is cost-prohibitive for many.
“The way things are right now, it is not economically feasible to make the big switch,” says Collin Steege, who custom-planted high-populating corn for himself and others in 2015 near Fredericksburg, Iowa.
Watch this video to see why Steege says twin 20 corn isn't as scary as it seems:
To aid farmers, Stine launched a 2014 planter program to entice farmers into the system. It worked with John Deere and Great Plains to make twin-row 20-inch planters in multiple sizes.
Participating farmers leased the planters on a multi-year lease-to-own contract. In year one, the grower paid a leasing fee roughly equal to 10% of the planter’s list price. In year two, the grower could exercise the right to purchase for an additional 23% of the planter’s list price. All planters that were leased in year one were purchased, although Stine currently have a handful of demo units still available.
“One way to make it more affordable is to get a 10-inch row planter like an inner-row Kinze and then do narrow-row corn,” says Steege. “Great Plains makes 10-inch drills you could set up for corn. I think that would be a cheaper way to get into it.”
Wider hybrid selection is also needed, says Moellers. “We only have five hybrids adapted to this area,” he says. He expects the amount of hybrids for this strategy to expand, though.
Stay tuned. “This is probably the most exciting year in my life with what we are doing,” says Stine.
What Industry Thinks
For a time, Harry Stine was out on a lonely limb of stratospheric corn populations. That limb is a bit more crowded these days, however.
“When you look at these things like drought-tolerant hybrids that all these companies say conserve moisture, what are they? Shorter plants,” says Stine.
Narrow rows planted at high populations aren’t new. “Ten years ago, there was a switch to 20-inch rows with plant populations around 45,000 plants per acre,” says Jason Webster, a Kempton, Illinois, agronomist. “But the corn fell over because of standability problems. The plants couldn’t stand that close together.”
That’s not the case with the specially designed hybrids for Stine’s twin-row 20s.
“I admire what he is doing,” says Bill Wyffels, president of Wyffels Hybrids. “He is leaping ahead of the steady progress that corn breeding has gone through in increasing 1½ to 2 bushels per year. What we see companies continue to stress is creating hybrids that withstand increased density and stress. Harry may get someplace with all this. But not everyone can do what Harry is doing.”
Twenty-inch rows showed little advantage in five years of Beck’s Hybrids tests. In 2014 and 2015, though, hybrids planted in 20-inch rows outyielded 30-inch rows. On a return-on-investment basis, improvements ranged from $18 to $51 per acre.
Industry still is keeping a wary eye
“We have watched the research, and we’re not sure if we advise growers to dive into it in a big way,” says Duane Martin, Syngenta commercial traits manager. “Research says there is potential there, but it may not be consistent everywhere.”
Why it works
Increased light capture is the reason Jerry Hatfield is bullish on high-population systems for corn.
“High-density systems can boost light capture canopy by 10% to 15% (over existing 30-inch-row systems),” says the director of USDA’s National Laboratory for Agriculture and the Environment in Ames, Iowa.
Twin-row 20-inch spacing helps ensure that sunlight hits the plants rather than the ground. Sunflecks – the amount of sunlight striking a surface – hits just 1% of the ground in a narrow-row system. “In a 30-inch-row canopy, the ground has 10% to 15% sunflecks. The increased light interception leads to increased total biomass and ultimately higher yields,” says Hatfield.
The hybrids’ small tassel size (one third that of normal) also helps.
“Large tassels contribute a 5% reduction in the amount of light captured during the growing season,” says Hatfield.
Early-forming canopies also help conserve early water use. “There is otherwise a large amount of bare soil (under 30-inch rows) with evaporation from the surface,” says Hatfield. Increased plant density intercepts rainfall and funnels it to the base of the plant.
An early canopy also decreases the rate of soil warming and allows more biological activity to occur at the soil surface.
“Crop growth is a direct function of water transpiring through the leaves that does not evaporate through the soil,” says Hatfield. “When the plant does not have transpiration, it does not have growth. Just a bit of stress can nip away at all sorts of things. On any given day, corn curls up a bit. When you do that over 10 days, it has a major impact on production.”
Soil temperatures also decrease. “In early June, soil temperatures can reach 130°F. to 140°F.,” says Hatfield. “We can spend lots of time warming the soil unnecessarily, causing problems with the biological and root activity. This causes numerous problems that are not beneficial to the soil.”
More N is Key
In 2015, Collin Steege’s twin-row 20s looked fantastic – right up until August. “Then I missed 18 days of rain,” says the Fredericksburg, Iowa, farmer.
Another yield killer was the missing segment of nitrogen (N). Steege did apply 160 pounds of N followed by 60 units over the top with a weed-and-feed application early in his corn’s growth stage.
However, his corn missed the last 50 units of N due to a tie-up of aerial applicators who were busy applying fungicide at the same time.
“Nitrogen management is the biggest thing,” says Steege. “That is what will get me my yield. To get the higher yield to pay for equipment, I have to advance in better N management,” he says.
Stine Seed Company researchers say 300-bushel corn requires 300 to 475 pounds per acre of N. It will require split applications to ensure adequate nitrogen throughout the growing season.
It’s particularly key to pair 1 pound of sulfur for every 14 pounds per acre of nitrogen that’s applied, advises Harry Stine, Stine Seed Company. “If farmers haven’t adjusted to the fact they need to add sulfur, the N will leach away if there is not sulfur to use for the corn crop,” says Stine.
In this video, Moellers explains how he changed his nitrogen sampling process when he switched to high population corn: