Then he puts on another 30-40 pounds of N through the pivot before tasseling. Prinz applies nutrients at varied crop stages through a starter at planting time and sidedressing a majority of his crops with UAN in early June, so the plants are fed what they need when they need it. "We have to be conservative with nutrients, so we are following the tissue sampling pretty closely." "Our farming practices have changed over the past two years," Prinz says. When corn prices were high, it was easier to apply plenty of nutrients. "Since more technology has been available over the past five years, we've also been tissue sampling the crop at 8 to 9 leaf, and applying nutrients through the pivot pre-tassel." "There is just less leaching when you feed what the crop needs," Prinz says. Spoon-feeding the crop is a main goal for Prinz. Today, Prinz applies nitrogen over all of their irrigated acres through fertigation, and sulfur over the sandier ground. Beginning in the late 1980s, Prinz's father began using their center pivots to apply crop nutrients. Todd Prinz farms and operates a family feedyard near West Point. With every input dollar under close scrutiny these days, fertigation offers one option, along with sidedressing, to supply crops with the nutrition they need at timely intervals. "You can put on 50 pounds of nitrogen with only a quarter inch of water."Īlthough Papenhausen is less likely to use fertigation in mid growing season this year because of the improved economics of sidedressing with urea, compared with the cost of UAN, he believes fertigation is an efficient use of pivot equipment. "And it doesn't impact their water balance at all," says Kranz. So, major water quality incentives come into play." Kranz suggests that providing nutrients through pivots as the crop is using them is better than losing the nutrients through leaching. "If you apply everything in the spring and have high rainfall, it could take some of the nutrients out of the soil profile. There are also nutrient management implications. Kranz says that safety has become an issue for some producers who simply don't want to work with anhydrous ammonia. "And, there is a labor cost of operating the machines to sidedress." You can always run into field conditions where you don't want to run a machine through the field," he says. "Depending on how many acres they have to cover, there is a small window of operation for sidedressing and most producers are using their pivots because they don't want to spend days in the field trying to get it done. For Papenhausen, whether he fertigates or not depends on the economics of the fertilizer. There are several reasons producers like Randy Papenhausen of Coleridge like having the option to use their pivots to apply crop nutrients like nitrogen.
FERTIGATION OPTION: Randy Papenhausen of Coleridge likes having the option of spoon-feeding his corn crop throughout the growing season by fertigating through his center pivot system.
However, Kranz says that the majority of chemigation permit holders are using their pivots to apply crop nutrients only through fertigation. Now, with fungicides entering the mix, they are being used to apply those more often." "With the advent of GMO crops, that number dropped off. "At one point, before GMO seed, there were a fair amount of producers using pivots to apply pesticides," says Nebraska Extension irrigation specialist, Bill Kranz. But pivots can be useful in more ways than one. When you think of irrigated crops in Nebraska, you automatically think of center pivots and watering the crops.