As input costs for corn production continue to escalate and farmers push for increased yields, it is vital that today's corn producers have an accurate assessment of the effectiveness both nitrogen and sulfur have on corn production when incorporated in starter fertilizer. In order to provide this information to producers, the Corn Marketing Program of Michigan partnered with Michigan State University to study the impact different variations of starter fertilizer have on corn production.

"The recent decrease in atmospheric sulfate deposition, increases in corn yields, and relatively early corn planting dates have prompted grower and industry interest in evaluating the use of starter fertilizer containing sulfur for corn," said Dr. Kurt Thelen, an associate professor in the Crop and Soil Sciences Department at MSU. To address this issue, a series of sulfur trials were initiated in 2005 and were continued during the 2006 growing season. Six study locations were evaluated in 2005 and 2006, including two sites on MSU research farms and four sites on producer fields. All sites had coarse-textured soils with minimum- or no-till cropping systems and were managed as a corn/soybean rotation except Ingham (continuous corn) and Tuscola (2006, wheat/clover cover).

"As a corn producer and an environmental steward of the land, I want to know exactly how the nutrients I apply to the soil will affect production on my fields," said Lyn Uphaus, CMPM president and a corn producer from Manchester. "I want to be able to optimize my corn production by applying the most cost-effective amount of nutrients. Research projects such as Dr. Thelen's, provides me with the data I need to make those decisions for my farming operation."

There were no trends in the data indicating there was significant response to the addition of sulfur in the starter fertilizer. Only three of the sites across both years showed a significant difference in yield resulting from the addition of sulfur to the starter fertilizer. "The yield responses observed in this study can primarily be attributed to the use of nitrogen, phosphorous, or a combination of both containing starter fertilizer in general, rather than from the addition of sulfur to the starter fertilizer blend," added Thelen. "As atmospheric sulfate deposition continues to decrease, a corn yield response to sulfur is more likely to occur. The likelihood of response should increase in cool, wet springs where mineralization is minimized and early crop growth is slowed."

"This research provides Michigan's corn producers with valuable information regarding the potential benefits of starter fertilizer and the effect of starter fertilizers containing sulfur," said Jody Pollok, CMPM executive director. "As a result, producers will have a better basis for deciding which nutrients to include in their starter fertilizer when planting corn, and which nutrients are most likely to result in a profitable crop response."

For more information on Dr. Thelen's research project or for more information on the CMPM, contact the CMPM office at (517) 668-2676 or online at www.micorn.org.