Looking across the checkerboard pattern of lush crops at the research station in Headland, Ala., one would never guess the land used to be predominately pastureland. Now cattle have returned for a different purpose — to boost peanut yields in the form of a bahiagrass rotation.
“This 48-acre field was highly unsuitable for experimental plot work,” says Dallas Hartzog, Extension agronomist and professor at Auburn University. “In the course of four years, we have made it into some of the most productive land we have.”
This multi-state project, proposed by researchers from Auburn University, the University of Florida, the University of Georgia and the United States Department of Agriculture, is designed to increase peanut and cotton yields by incorporating cattle into a four-year rotation that consists of two years of bahiagrass followed by a year of peanuts and a year of cotton.
Most vital to the success of the rotation is bahiagrass, says Hartzog, who pioneers the research in Headland, Ala., one of the four research sites in Alabama, Georgia and Florida. “The reason the Southeast has not seen peanut yields increase is because the soil organic matter has been depleted. Planting bahiagrass increases the organic matter content, which affects root penetration and crop yield.”
With the current dip in peanut and cotton prices, now is the ideal time for peanut producers to implement a new system, says David Wright, University of Florida Extension agronomist and professor. “If growers are looking at a system they can actually net more money from than they actually put in, this is it.”
The rotation is a great way for peanut producers to take advantage of a strong cattle market, Wright says. “The cattle add a lot of economics to the system. Your returns will be two to five times higher on the farm because you can graze on planted winter annuals and summer bahiagrass. You'll reduce your risk significantly.”
In addition to diversified risks and increased profit from grazing cattle, Wright says the rotation does wonders for peanut yields and cotton growth. “Bottomline, we averaged 1,200 to 1,500 pounds more peanuts per acre with bahia. Peanuts and cotton showed better top growth and root growth with bahia.”
In addition to crop yield and plant growth measurements, Wright and his colleagues also measured water infiltration, soil moisture, soil nitrates, bulk density, diseases, soil conductivity, compaction and earthworm populations. “In everything we've looked at, the bahiagrass system far exceeds the annual cover crop system of cotton and peanuts with winter annuals and strip-tillage. We've witnessed better water infiltration, fewer soil nitrates, decreased leaching, less compaction and less soil bulk density.”
One aspect of the project Wright is particularly fond of is the conversion from a standard pivot irrigation system to a variable rate irrigation system. “It is a computer-controlled application system based on soil conductivity. Wet areas receive less water and dry areas more water. We have decreased water use by 20 percent.”
Wright says they are also using the variable rate system to measure fertilizer effects. “With fuel prices as high as they are, using this system for fertility measurements may benefit farmers economically.”
By having half of the land planted in bahiagrass, Wright says farmers will see benefits at planting and harvest. “You are not only cutting planting and harvest time in half, you are also reducing reliance on favorable weather and adequate moisture. While cattle don't mind a good hurricane, other crops could suffer greatly.”
Though two schools of thought exist on when bahiagrass should be killed, Wright says research suggests killing in the fall is preferred over killing in the spring because of the amount of time it takes for bahiagrass roots to decompose. “It takes several months for decomposition, and our penetrometer readings that measure the soil compaction level are much lower for the fall kill. We've had much higher yields with a fall kill.”
According to Wright, this rotation is the next step after conservation-tillage and allows producers to fully engage available resources. “It turbo charges the conservation-tillage concept and allows year-round utilization of the farm resources with the land, with much less money laying on the line every year.”
In addition to its benefits for soil structure, sustainability, and resource use, Hartzog says the rotation is also useful for lowering production costs. “There is not a grower who is unaware that his inputs are going up. We're gathering data regarding the benefits of bahia for the soil, but we're also making high yields and proving that this is a system that should be of interest to every peanut farmer.”