Should I Include Sulfur For Soybeans Or Only For Corn?
May 20, 2011
Question: I'm in a corn, corn, soybean three-year rotation and currently am only applying sulfur on the two years of corn. Should I be adding it to the bean year? Or, would it be available to the beans if I were to up the rates to more than what the corn needs in the corn years?
Answer: A 200-bushel per acre corn crop has a sulfur removal rate around 15 lb/A. In recent years there has been a greater yield response to applying sulfur for corn production. Soil fertility specialists believe the sulfur response is increasing because of the reduction of sulfur atmospheric deposition (cleaner air, less pollution). Also, fertilizer sources are cleaner (less incidental sulfur in them) and with fewer manure applications. Soybeans are typically not very responsive to sulfur applications. Generally, soybeans can maintain adequate levels in the plant by using residual levels from the soil. I would continue applying sulfur just for your corn production and not the soybeans. However, it may be helpful to pull some tissue tests in soybeans to verify adequate levels. Sulfur fertilizer in general is very mobile in the soil and would likely not be available in subsequent years.
Be on the lookout for sulfur deficiencies in your crops.
You can easily misdiagnose this problem.
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