Watch: High Yields Equal High Sulfur Demand in Corn and Soybeans
Corn and soybeans are two crops with a high sulfur demand.
WATCH the latest episode of Keg River TV as independent agronomist Ray Dowbenko explains that it’s the push for high yields that drive high sulfur application rates.
On a unit basis, and depending on location, a bushel of corn is going to take between 0.1 and 0.2 pounds of sulfur, says Dowbenko, an independent agronomist and crop consultant. A bushel of soybeans is going to require between 0.3 and 0.4 pounds of sulfur.
“If you think of your typical production rates of about 200 to 300 bushels of corn and 50 to 70 bushels of soybeans, you can see you’re going to need a lot of sulfur,’’ says Dowbenko.
Ensuring ample sulfur at key growth stages
Sulfur is important in amino acid formation, the creation of proteins, and chlorophyll production. It also promotes efficient nitrogen use in corn, and nitrogen fixation and nodule formation in soybeans. “Sulfur not only impacts growth but also profitability,’’ says Dowbenko.
Corn takes up about half its sulfur to the tassel stage and the other half to grain fill.
With soybeans, about half the sulfur uptake occurs by the R2 to R4 reproductive stage – from full flower to full pod – and the other half is taken up to grain fill and pod fill.
The season-long availability of elemental sulfur means it oxidizes to feed the crop throughout the growing season. It is important to support this by ensuring there is an immediate sulfur source to meet initial demand at the early growth stages.
Leaching can be a concern with sulfate fertilizers. Dowbenko says a lot of corn is grown on sandier ground that’s either irrigated or rain-fed. Water will move sulfate sulfur down through the soil profile and below the root zone. Not so with elemental sulfur.
“Elemental sulfur that oxidizes is available for crop uptake, and what hasn’t yet oxidized is resistant to leaching.’’
Part 1 of a 2-part episode.