Following a series of heavy rainfall events across Nebraska, many corn growers are asking questions about how much nitrogen is left in the bucket. Mike Zwingman, Agronomy R&D Manager at Central Valley Ag (CVA), says now is the time to do your homework – that is, assess the situation with soil testing, and make an adjustment properly rather than making an in-season application based on gut reaction. "If I've learned anything, I can't trust my gut when it comes to nitrogen loss," says Mike Zwingman, "I have to go out and experience what's going on and put in the work."

In the latest Nebraska Notebook, a podcast focusing on critical crop-related issues in Nebraska throughout the growing season, we visit with Zwingman on nitrogen management – whether it's mitigating loss before it happens, or adjusting nitrogen management in-season.

Nitrogen models – one of the many tools in the grower's toolbox – are part of this equation, and Zwingman notes this year, CVA is trialing five different modeling tools to see how each one responds to the same scenario, including rainfall events and different application timings. "I don't think any of them [nitrogen modeling tools] are wrong. It's about understanding the quirks of every different tool and how they operate," he says. "We have more tools in our toolbox today than ever before, it's just a matter of finding out which tool is right for your operation and how you go about making decisions, because I think they have different fits for different growers."

And when it comes to optimizing nitrogen efficiency, Zwingman encourages growers to think about nitrogen on a pounds per bushel basis, rather than pounds per acre. "When we start looking at pounds per bushel, we start driving to that acre level of accuracy," he says. "Really, what I see when we start doing this is a mindset of actually understanding the profitability of every acre we farm."