The 43rd North Central Extension Industry Soil Fertility Conference was held in Des Moines earlier this week and your Monitor was in attendance. The annual conference is organized by the International Plant Nutrition Institute and is geared toward research, giving academics a chance to share their findings and discuss them with their peers. I will give you the full run-down in this week's blog, later today, but what I saw there was not what I expected.
Despite the wide range of presenters on hand, the overall message was rather narrow, focusing almost entirely on nitrogen reduction. Two different representatives from USDA/ERS spoke about nitrogen management and suggested methods for maximizing nitrogen efficiency.
A leading researcher from the University of Illinois said in his speech a grower cannot expect to put down 250 lbs of N and get a 250 bu. yield. His and other presentations highlighted the terminal N response level in corn suggesting there is a sweet spot for maximizing yield and any application above that amount is wasted money and wasted nutrient.
The biggest takeaway, in my mind, was the suggestion of a shift, inspired by nutrient reduction and encouraged by low corn pricing, toward increased N utilization in developing crops which is expected to decrease N application rates. A better understanding of the growth cycle of corn would allow growers to pinpoint phases of crop development in which nitrogen uptake is at its peak. Fall applications of anhydrous may be replaced by cover crops with a portion of N applied in the spring with sidedress at different points of the life of the plants.
Many growers already include in-season sidedress as part of their nutrient strategy and as more farmers adopt a split-application approach, nitrogen rates applied will fall. The key is to encourage crop N utilization, saving the grower on expensive nitrogen, and helping EPA -- and now USDA/ERS -- to keep nitrogen out of the watershed.
The regulatory environment is changing and application methods were suggested as a means to reducing the nutrient footprint in the nation's watersheds. We will talk more about all of this in the coming weeks.