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Reduced soybean seed rates don't limit yields
MISSISSIPPI STATE -- Soybean producers are learning that planting fewer seeds can mean higher profits.
Rising seed technology fees are encouraging soybean producers to be frugal as they plant.
Soybean seed costs about $26 to $27 a bag this year, but there is speculation it will rise to as much as $35 as seed companies pass on a higher cost of research and development.
"We've always had the tendency to over-plant. It's just been our nature," said Alan Blaine, soybean specialist with the Mississippi State University Extension Service. "For 12 years, I begged growers to fine-tune planting equipment and plant fewer seeds, but not many listened. With prices rising to about 60 cents a pound, they're listening now."
Blaine said soybeans have a tremendous capacity to compensate for thin stands, and with proper variety selection, growers can plant fewer beans and still see the same yield.
"A lot of the reason we used to plant heavy populations was for weed control," Blaine said. "We don't need that any more because we have good herbicides available."
Blaine said early-planted soybeans should have 130,000 to 160,000 plants per acre and 100,000 to 130,000 for later-planted beans. Actual planting rates are individual decisions made based on soil type, land preparation, variety, weather forecast and more.
"You don't have to cover many acres with a reduced seed rate before you can buy a new planter with the money you save," Blaine said.
Charlie Stokes, area agronomic crops Extension agent working out of Monroe County, used a 30-acre demonstration plot last year to introduce producers to the concept of reduced seeding rates. Forty pounds of Roundup-Ready soybeans were planted per acre with a vacuum planter. The producer who owns the field usually planted 60 pounds an acre with a grain drill.
"At harvest, the soybeans yielded an average of 50 bushels an acre, which equaled the producer's best-ever average while planting 60 pounds of seed per acre," Stokes said.
This field netted a per acre seed cost savings of $10 while yielding the same harvest.
Stokes said reduced soybean seeding rates are suited to a wide-row system planted with a precise planter. Seed treatment is very important, and he recommended growers select a soybean variety that branches out and fills in the space between plants.
Mack Young, Quitman County Extension director, convinced two area producers last year to plant four to five seeds per foot of row rather than eight or nine as they had been planting. They planted about 30 pounds of seed per acre rather than 45 pounds.
"Average yields for both producers were above 40 bushels per acre, which was comparable with the higher seeding rates they had been using," Young said.
He said these producers saved nearly $8 an acre using the lower seed rate on 2,000 acres.
"Whether you have four or nine plants per foot of row, there's not going to be a bean's difference in yield," Young said. "The fallacy of planting more seeds is if you don't get a stand from planting six seeds, conditions won't let you get one from planting 10 to 12 seeds."