Farmers face more weather extremes nowadays than in the past. Weather-related impacts on fertilization application can be both good and bad.
It is becoming increasingly important to make informed fertilizer rate decisions as nitrogen fertilizer costs and environmental concerns increase. A new model study by the University of Illinois examines soil nitrogen dynamics and crop yields at the end of the growing season.
Ziyi Li, a doctoral researcher at U of I and lead author of the new study “Assessing the impacts of pre-growing-season weather conditions on soil nitrogen dynamics and corn productivity in the U.S. Midwest,” said, “When farmers plant corn in spring, they already know what has occurred during the pre-growing season.”
Using an agroecosystem model called ecosys, Li examined the relationship between soil inorganic nitrogen content, yield, temperature, and precipitation in the growing season.” the study shows farmers can apply fertilizer based on pre-growing season information,” said Ziyi Li.
When farmers did not apply the spring fertilizer, the crop yield decreased by 5 to 14% due to nitrogen leaching. We discovered in the study that due to heavy pre-season precipitation, the 2018 Illinois yield dropped 1 to 3% even when we applied 150 lbs of nitrogen per acre.
“Our model suggests that adding 16 lb more nitrogen could prevent a 1-3% yield loss if an Illinois farmer applied 150 pounds of nitrogen per acre,” Li said.