A well-calibrated yield monitor can assess yields to within +/- 3%, says Matt Darr, a precision agriculture specialist at Iowa State University. A poorly calibrated monitor can have a margin of error of +/- 10%, particularly in fields where yields vary significantly.
The two-part program includes planning tools to develop field-by-field nitrogen management strategies that reduce the chance of over-fertilization. The tool also can be used to assess current soil nitrogen levels and risk status throughout the growing season.
In 2014, the Boettgers, who farm 3,000 acres near Harlan in southwestern Iowa, decided to harness technology to help solve their planter down-pressure challenge. They outfitted half their 16-row Kinze 3600 planter with an Ag Leader hydraulic down-force system, which automatically senses down force and adjusts it in one second.
Fields across the Midwest will begin sporting a new look in 2015 as farmers begin using variable-rate, multi-cultivar planters, which are available commercially for the first time after being field tested in 2014 by Kinze Manufacturing and Precision Planting, in conjunction with four seed companies.
After two years of testing data-driven, variable-rate crop management programs on their farms, Rick Niese and Jeff Heepke are planning to continue their efforts in 2015 in hopes of further ramping up productivity.
Last year produced red-hot yields for Mike Rosenbohm, who farms near Graham in northwestern Missouri. His average corn yields were up 20% from his long-term average, with yields ranging from 180-225 bushels per acre. So when a narrow-row, high-population test field had a corn yield bump of 30% or more compared to nearby corn planted in 30-inch rows, he signed a contract to purchase a narrow-row planter.
Forecasting higher-than-normal rainfall several months in advance is still folly. But from a climatological standpoint, odds are that wet springs and summers are more likely in the years ahead than they have been in the not-so-distant past.
Following the worst drought in his farming career – and growing frustration over competition for land – Les Albrecht expanded his operation internally in 2013 by adding five circles of irrigation to his dryland operation.
Bob Little, who farms near Hebron, says harvesting corn at 22-25% moisture consistently boosts yields. Part of the increase is due to reduced field and harvest losses, which account for 5-10 bushels/acre. But another factor – the mitigation of unexplained dry matter losses, often called phantom or invisible losses – also is at play, he says.
“Many farmers don’t fertilize for sulfur and zinc. And many people don’t realize the season-long importance of phosphorus,” says Fred Below, a University of Illinois plant physiologist. In research conducted by Below and graduate student Ross Bender, extra P, S and Zn increased corn yields 8 to 10 bushels per acre in fields already supplied with a balanced high-yield fertility program.
Three key nutrients’ under-recognized importance – sulfur, zinc and the long-recognized standby, phosphorus – could limit corn yields from an otherwise well-fertilized corn crop, says University of Illinois Plant Physiologist Fred Below.
As weather extremes become more common, the Alversons, who farm in South Dakota, have taken steps to protect their farm’s productive capacity. They’ve added drainage tile, plus irrigation on fields with lighter soils. They’ve also retooled their equipment lineup for quicker planting.
Top-yielding no-till winners rotate with soybeans, select hybrids for early vigor in no-till conditions, scout for early season insects and optimize fertility and application timing, including micronutrients and fungicides, to achieve 300-bushel corn yields.
Tillage, at one time a go-to solution for loosening compacted soils, also creates poor soil structure and hardpan soils. “There is a downward spiral with tillage. The more you till the soil, the more you destroy its structure," says Jim Hoorman, Ohio State University. While deep ripping or vertical tillage offer a short-term solution, the long-term answer to soil compaction is to rebuild soil structure, says Hoorman.
Denny Friest has conducted dozens of trials since 2000, and takes on several new comparisons each year through a program with Iowa Soybean Association. Participating farmers work with researchers to design practical trials. Farmers across the state often conduct trials on similar topics, such as N fertilizer or fungicide performance, which enhances results’ reliability.