50,000 plants per acre
BY KAREN SCHWALLER
ADEL – Trying to get the most grain per acre is something that is not new to growers.
But the ways growers go about doing that could soon be changing as Stine Seed Co. looks for what it calls “the next big thing.”
David Thompson, national marketing and sales director for Stine, said the company has been experimenting with 12-inch corn rows, equidistant plant spacing and corn genetics able to withstand 50,000 plants per acre.
He said, the results showed it’s an experiment worth pursuing.
“As a company we have always been a little ahead of the curve in terms of planting with higher-than-average populations,” Thompson said. “Harry Stine, our founder, is a farmer himself and he believes whole-heartedly that this is the way the industry is going to go.
“We’re very excited about it.”
Stine Seed has been working in 30-inch and narrower rows for more than 15 years, while at the same time experimenting with genetics that perform well under high plant populations.
During the 2012 growing season, the company planted 2,500 corn acres in 12-inch rows at its research fields in Dallas County, using Stine 9733 BT3 Pro seeds – along with a specially-designed planter for such narrow rows.
Each plant was spaced 10 to 12 inches apart. This plan is opposed to contemporary 30-inch row widths, with seeds being planted three to four inches apart.
Thompson said with the 12-inch row configuration, plants undergo less stress from competition for moisture and nutrients, since all plants are equidistant from each other.
He said when hybrid corn was introduced in the 1930s, plant populations hovered around the 8,000 plants per acre mark.
Today in Iowa it’s quite common to see fields planted at 32,000 to 34,000 plants per acre, a four-fold increase.
Yields in the 1930s were around 37 bushels per acre, while today, 150 to 160 bpa is common with average soil.
Thompson said the data showing the amount of grain per plant has remained constant since the 1930s – with plants yielding about one-third of a pound of grain per plant. Since that number remains constant, Thompson said the only way producers can gain yield is more plants per acre.
“When you chart it out there is a direct correlation between plant population and yield,” Thompson said. It takes eight to nine years to develop a new hybrid product, he said.
“If we want to have hybrids that growers will want to plant in 2020, we have to be starting them on that path today and developing (genetics) for that,” Thompson said, adding that stalk height, standability and foliage are all factors in developing genetics that will give growers the kind of genetics they need to be successful at planting more plants per acre.
They are developing corn hybrids for higher population planting, designed to grow narrower, with leaves that grow more upward instead of out; and stalks that are shorter.
“From a breeding standpoint, if you can avoid the competition factor, whether weeds or other corn plants, the better off you are,” he said.
But how much corn can be planted in one acre?
“If you have 12-inch rows, you have true equidistant plant spacing. You can plant about 43,560 plants per acre, so basically, you’d have one plant per square foot,” he said. Stine planted 51,000 seeds per acre, ending up with about 48,000 plants per acre in their final stand. Their seeds were dropped about 10.5 inches apart, so he said they were crowding their own theory somewhat.
“Once you subscribe to the fact that you’re only going to get so much grain per plant, and wonder what to do to get to 400 bushel corn, the answer is you have to plant 67,000 plants per acre,” Thompson said. “To push yields to where people want to go, you’re going to have to have more plants per acre.
“There’s just not any other way to do it,” he said.
Thompson said Stine planted a specific corn genetic in what he called elite plots last year at variables of 40,000, 50,000 and 60,000 plants per acre.
“This particular product continued to provide higher yields at every step of the way, providing its highest yield at 60,000 plants per acre,” Thompson said. “That told us the yield potential for this is unlimited, at least in the range that we’ve looked at.
“That’s what really started the wheels in motion and we thought that if we have genetics that are that fluid and can move that way, then we should be testing that, and understanding that you can only push it so far in a 30-inch row before you just have those plants too close together.”
Stine Seed acquired a 60-foot, 60-row planter constructed by Bauer Built in Payton. It featured John Deere twin-row units with experimental brackets.
Stine contacted Marion Calmer from western Illinois when it sought harvest equipment. Calmer has a patent on an innovative gear box design, Thompson said, which operates like a conventional row crop head, but instead of two gathering chains, Calmer’s has one per side.
“You’re space-limited when you have 12 inches between rows,” Thompson said. “You only have so much room for equipment.”
Stine used one of the heads built in Calmer’s shop, and two heads that were built in its own shop to Calmer’s specifications. They were 20-foot, 20-row heads.
Thompson said the yield results spoke for themselves.
“Yields were suppressed because of the drought and heat stress,” Thompson said, “but we saw yields that were better than our 22-inch rows, so 12-inch rows were holding their own and in many cases were actually out-performing.”
In Stines’ Perry field, combine monitors were reading in the mid-200 bpa.
“They had an extra inch of rain that we didn’t get here,” Thompson said, “so yields were better there across the board than (in Adel), but 250 was significantly better than most people were seeing in that neck of the woods.”
Those numbers, he said, don’t seem extraordinary, but taking into account the kind of growing conditions grain producers faced this year, and understanding that it worked in a year like we just experienced, Thompson said the company tested “the bottom.”
“If it can work there, it should be able to provide greater returns when you have better conditions,” he said “We believe the theory works and yet we don’t want to give growers the impression that we need to push everybody toward 12-inch rows tomorrow.
“The test we did here involved only one hybrid, and we have more genetics coming out of that lineage, so as time goes on we’ll see more of that similar strain of genetics coming forth.
“But there aren’t very many types of genetics on the market today that growers can take out and plant at 50,000 plants per acre. The industry is not there yet.”
He said producers thinking about narrower their rows should consider the direction the industry is going, and think far ahead of the game, since equipment to change over is expensive.
“We’re in the beginning stage of developing a good body of data to demonstrate what we’ve seen and to be able to demonstrate what we think the potential for this is,” he said. For a lot of growers, this has already been on their minds, but even the equipment isn’t there yet to make it happen.
Equipment companies and genetics need to work together to make this concept work, he said.
“As we look at the data and how it all lays out from start to finish, it becomes nearly impossible to argue where this thing is going,” Thompson said. “Everybody’s saying it all makes sense, but somebody has to move it forward.
“There are a lot of players involved. It’s a great concept, but we haven’t sold a lot of equipment or seed at this configuration. It’s coming, though.”
Thompson quoted company founder Harry Stine, who said the four-fold increase in plant population over the last 80 years has happened “almost by accident.”
“No one understood what this correlation was, but if you look at where we’ve gone in 80 years, and now think about what we can accomplish in the next 20 years, we’re excited about it. It’s generating a lot of conversation.”
Thompson said that not all producers are believers right away, but that it’s OK.
“We’re doing things so that we can have the products for the next decade; we’re trying to see the future,” he said. “With commodity prices as they are today, growers are definitely looking at more alternatives.
“The rate of return (on 12-inch rows) is pretty good, so if (growers) can get an extra 4 to 5 bushels of corn per acre, spread over the farm, it’s looking pretty good.”