Examining Sulfur Rates for Wheat & Split Application versus a Single Split Broadcast

Decreased additions of sulfur to the atmosphere through low sulfur diesel fuel and reductions in industrial emissions have lead to a decrease in incidental deposition of sulfur for crops. This has left some to question if sulfur needs to be supplied to most crops as fertilizer. Current recommendations for sulfur fertilizer applications in Minnesota are limited to sandy soils with low organic matter contents. A single broadcast application of 2 lbs of sulfur or 0 to lbs applied with the drill is typically sufficient in sandy soils. However, responses to sulfur in corn grown on fine textured soils have lead to questions about other crops. In fine textured soils the organic matter generally will mineralize around 4 pounds of sulfur per percent organic matter based on previous work in Minnesota. These rates are generally enough to maximize yields for most crops. Sulfur is essential in plant and grain protein which can be important in crops such as wheat that are sold based on their quality. Therefore, it is important to study sulfur response in light of the current situation to make sure not only yields, but also grain quality is being maximized, and whether the current recommendations are relevant for the current environmental conditions around the state.