To increase the usefulness of this project to Illinois farmers, Fernandez needs volunteers throughout the state who would like to participate in an on-farm research study to measure corn response to sulfur fertilization.


Fernandez says all soil types will be considered, but his team is especially interested in light-colored soils (less than 2% organic matter, coarse texture or both) and soils with an eroded phase. The only soils that will not be considered are soils that have received manure or sulfur applications within the past five years.
Volunteers conducting these trials will follow a simple design applying 0 and 30 lbs. sulfur/acre as a broadcast application in a uniform portion of the field. A minimum of three replications, or as many as eight replications, are needed for each field. It will be important to georeference or clearly mark each strip with different color flags or markers in the center of each strip, Fernandez says.


Strips can be eight to 16 rows wide by 300-1,000 ft. long. The size of the strip must allow accurate application of the rate, accurate measurement of yield and, if possible, be wider than the harvest strip. However, if the combine is at least 12-16 rows wide, it is possible to harvest the strip without having border rows.


U of I researchers prefer the use of ammonium sulfate (NH4)2SO4 (21-0-0-24); MicroEssentialsTM sulfur (ME S) ME S15 (13-33-0-15); or elemental sulfur (0-0-0-90). If the sulfur source contains other accompanying nutrients, the corresponding rates of those nutrients will need to be applied to other treatment strips to avoid a differential response to nutrients other than sulfur.


“Applying treatments this fall would definitely be an option,” he says. “However, our preferred application time is the spring (preplant), but we understand that fall might be the only option for some farmers.”


The only data volunteers will have to provide is the yield for each strip. This information can be collected by yield monitor or from a weigh wagon. Volunteers will not be required to take plant or soil samples, but would need to allow the researcher to visit the strips two to three times during the growing season.


“The better coverage of the state we have, the greater our ability to predict where sulfur applications are most needed,” he says.


For more information, contact Fernandez at or 217-333-4426, or check out the Oct. 7 edition of The Bulletin, an online publication written by U of I Extension specialists in crop science.