Yields are up by half, water filtration has increased and profits are up three to five times.
All this is made possible by adding a little grass and cattle to the typical cotton-peanut rotation.
David Wright, a University of Florida agronomist calls the bahiagrass-based rotation “the next step after conservation-tillage” in increasing yields and profitability.
“A sod-based system is a year-round project, using labor and equipment and soil for the entire year,” Wright told a group at the 27th annual Southern Conservation-Tillage Conference held in Florence, S.C.
“While conservation-tillage has resulted in many benefits, farmers still struggle since yields have not necessarily increased when they converted to minimum-tillage,” Wright says.
That could be about to change.
“There is a next step in increasing yields,” Wright says. Years of research in the Southeast show the benefit perennial grasses such as bahiagrass can off to improve soil structure and reduce pests and increase crop yields.
Over the last five years in Georgia, Florida and Alabama, researchers have used a two-year bahiagrass rotation with peanuts, cotton and winter grazing with the idea of stepping toward increasing yields in conservation-tillage. Researchers have plans to expand the project to include other states as well.
“Perennial grasses are taking cover crops a step further,” Wright says. By using the bahiagrass as winter grazing for stockers, farmers could add an additional stream of revenue to the operation.
For the row-crop operation, two years of bahiagrass in the rotation set up the cotton and peanuts for success.
On the yield level, researchers had peanuts producing 1,500 pounds more than the conventional rotation, with fewer diseases and pests. Cotton yields were also higher.
“The soils are more mellow,” Wright says. “There's more root area and length with peanuts and cotton behind bahiagrass than the cotton-cotton-peanut rotation.”
For cotton, the bahiagrass rotation means 50 percent more biomass, and 50 percent higher nitrogen uptake, leading to a root system that is larger by half than the roots on a typical rotation. In addition, a larger root system leaves channels that increase soil quality and the number of earthworms in the soil.
Sod-based systems aren't easy, however. And farmers have been slow to adopt them, Wright says. “Farmers ask how they can afford to put in bahiagrass on rented land?” The answer lies in its benefits.
He points to increased water filtration and soil quality as talking points with landowners. “Sub-soil moisture is much higher in the bahiagrass system — that means less water we need to pump on the soils,” Wright says. “Roots in the bahia system had punched through the compaction layer. And we found earthworms in the soil after bahiagrass.”
He advises killing or tilling the bahiagrass in the fall before spring planting. “Don't just strip-till in the spring, kill it in the fall.” Research showed no difference in peanuts yields “strip-tilled” into bahiagrass or planted into “turned” land. On peanuts, researchers saw a 50 percent increase in yield and grade — they also found no problems digging the peanuts.
“By the fourth year of the sod-based rotation, peanuts yields are higher and cotton yields are higher,” Wright says.
Researchers continue verifying the benefits of the system and moving it onto farms.
Wright presented research he coauthored with James Marois, Tawainga Katsvairo, Pawel Wiatrak and Jim Rich of the University of Florida.