Bermudagrass growers can save money by splitting nitrogen applications, suggested Dennis Hancock at last week’s Hay Production School in Waynesboro, GA.
Hancock, University of Georgia extension forage specialist, spoke to about 100 Georgia and South Carolina growers on cost-effective fertilization strategies.
“Usually on a long-term average, splitting nitrogen applications rather than providing a one-time nitrogen application will generate between 1,200 and 2,400 lbs/acre additional yield,” he said. “That strategy also increases nitrogen-use efficiency by 25-30%, which can be a big deal both economically and environmentally.” Splitting nitrogen applications can also be beneficial when drought hits.
“Another topic of concern is our inability to get reliable sources of ammonium nitrate,” Hancock said. “We’ve been comparing different nitrogen sources. As producers look to reduce their nitrogen rates, and as we get down into those lower rates, urea-based products are less efficient at the lower rates. We are both reducing our rate and we are reducing our effectiveness at that rate.”
Georgia hay growers have been showing interest in integrating legume crops with bermudagrass, either with annual crops such as crimson clover, or by interseeding perennial legumes such as alfalfa into the bermudagrass. “The annual legumes can add between 75 and 100 units of nitrogen during the winter, then the nitrogen is released during the following production year,” Hancock explained. “Generally speaking, the perennial legumes we would grow as a companion crop, like alfalfa, would provide yields equivalent to adding 200 units of nitrogen. That is a significant amount of nitrogen added to the system.”
Hancock pointed out there can be management challenges when mixing bermudagrass and alfalfa. The extent of the mixing strategy’s success is somewhat site-specific.