Corn undergoes a period of rapid nitrogen uptake after the V8 growth stage and through tassel and silking. If nitrogen is not readily available to the corn plant as it enters this period, it can limit yield potential.
With UAN, this is especially applicable to the urea portion of the fertilizer (comprising 50% of the UAN), which has to be converted into ammonium before the plant can use it. Enhancing a sidedress UAN application with Extract PBA, which accelerates nutrient mineralization and recycling, can ensure that the crop has the nitrogen it needs in that 21-day period of rapid uptake without falling short.