A popular commercial that ran for years touted the slogan “Beef. It’s what’s for dinner.” It helped cattle producers sell lots of beef. When it comes to corn, “what’s for dinner” is easy — it must be nitrogen.
In today’s current cropping conditions where margins are tight, nitrogen is one of the highest-cost inputs in corn production. How can you improve nitrogen efficiency and maximize dollars spent, helping to reduce inputs?
Markets are variable and hard to plan for, but finding ways to reduce costs or become more efficient with inputs can help with profitability. I’ve spent time working with farmers who want to improve their N efficiency and profits while maintaining yield.
The first step may be simple. Apply nitrogen as close to when the crop needs it as possible. This is both an economic and an environmental decision. Corn needs nitrogen in June and July, not in November before you plant the next spring. Even early-spring application or preplant nitrogen is susceptible to unpredictable weather conditions. Heavy rains or unseasonable temperatures can cause valuable nitrogen losses to denitrification, leaching or volatilization.
While fall application may be easier from a labor standpoint, it’s not the best choice from an economic, agronomic or environmental perspective. Using split applications of nitrogen at planting with a second application later in the growing season, when the corn needs it, is a better option.
Again, though it requires more labor, time and management, “spoon-feeding” nitrogen with multiple application passes and maybe in multiple forms can provide N to the plant during the time of highest demand. This also allows for application of micronutrients that may be in demand later in the growing season.
Farmers I work with say they’re finding some newer “racehorse” hybrids take up available nitrogen much later than older hybrids. They may need nitrogen all the way to black layer if the N is adequately available in the soil, and corn plants are healthy and free of stress.
There may be some yield and economic advantages to the way nitrogen is applied. Some research suggests that using high-clearance equipment with Y-drops to get the nitrogen closer to the row has advantages versus traditional sidedress coulter or knife application. This may be especially advantageous in dry years, when corn may struggle to access the nitrogen that’s farther away from the plant.
The best way to find out what works for your farm is to try different things. Experiment with different rates of N, apply at different times of the year, or have a neighbor or local ag dealer demo different equipment. It doesn’t need to be on a large scale — just a few acres with different treatments. There is no better way to test new methods than to do so on your own acres.
Harrison is a district conservationist with the Natural Resources Conservation Service. He writes on behalf of the Indiana Conservation Partnership.