CHAMPAIGN, Ill. — Using starter fertilizer on three Illinois no-till farming sites during the past three years has produced economically desirable returns that compensate for the initial investment of equipment and supplies, university agronomists say.
The experimental fields produced up to 14 additional bushels of corn per acre, said Karl B. Ritchie, a University of Illinois doctoral student in agronomy, in a report given Nov. 6 in Indianapolis at the 1996 annual meetings of the American Society of Agronomy, Crop Science Society of America and Soil Science Society of America.
The study is the first hard look at the economic benefit to farmers who choose to use starter fertilizer, which has been shown to boost yields in no-till fields that have been studied in Illinois and Indiana by the U. of I. and by Purdue University, respectively.
No-till corn, in particular, often starts growing slowly because of cool, wet soils early in the season. Starter fertilizers provide farmers the chance to increase early nutrient availability.
In Ritchie’s tests, the best results consistently were obtained with starter fertilizer containing a nitrogen and phosphate blend applied by what’s known as the 2X2-banded technique (2 inches to the side of the seed and 2 inches below the surface).
The earnings from the additional bushels produced by the technique were enough to offset the estimated $1,000 per row cost initially spent on equipment and fertilizer, said Robert G. Hoeft, a professor of agronomy and faculty adviser on Ritchie’s research.
"The fertilizer is not cheap," Ritchie said. "The steel on a planter is the big cost, about $1,000 per row. That’s a big investment. But if you’re looking at 500 acres of corn with a 10-bushel yield increase, that’s a $30 an acre return, assuming $3 corn, and that adds up fast. The attachment is not just used one year, so your return will continue in subsequent years."
Because the return on investment was consistent across so many locations, Hoeft said, "I really feel pretty strongly that no-till farmers ought to consider the use of starter fertilizer."
The research was done across Illinois, between Ashton and Dixon in the north, near Gridley to the north of Bloomington and near Oblong in the southeast. A site near Pana, west of Shelbyville, also was included, but rain washed out the experiments. The soils are typical of those found in the Midwest.
The researchers also analyzed the use of less-expensive surface-applied starter fertilizer, finding increased yields but not as significant, nor as much economical benefit, as those gains from the 2X2-banded treatment. They also concluded that soils with low potassium levels could be improved by using potassium in the starter if potassium is not used in an initial broadcast application; in two of three years at Oblong, there was no response to potassium when potassium already had been broadcast.
University of Illinois at Urbana-Champaign. November 1996.