Great things many times evolve from small beginnings. Such can be said about the rapid expansion in recent years of strip-tillage farming in north Florida's Santa Rosa County.
"Back in 1996, our county had only 200 acres of strip-tillage production, and 80 acres of those were mine," says Paul Griswold, one of the area's pioneers in conservation-tillage farming. "That number increased to 3,000 acres in 1997, 10,000 acres in 1998, 15,000 acres in 1999 and an estimated 20,000 acres this year."
Santa Rosa County now is one of Florida's leaders in strip-tillage production, especially of peanuts and cotton, said Griswold, speaking at the recent Southern Peanut Growers Conference in Panama City.
"I got into strip-tillage primarily because of wind erosion," says the Panhandle grower. "Sand was cutting down my cotton. The savings in time and labor also were factors. We have two men farming about 3,000 acres, so it's helpful anytime we can take out another trip across the field."
In a county that consists almost entirely of dryland production, growers also like the moisture retention benefits of strip-tillage, he adds. "Strip-tillage either works, or we've fooled a whole lot of people in our county. I believe it works, and I plan to stay with it in some form or fashion. We learn something new each year, and we make changes as we go."
For growers who are considering converting to strip-tillage next year, and who intend to plant a cover crop this fall, Griswold recommends planting a cover on the lower end of the seeding range.
"We prefer a wheat cover crop. I wouldn't use an annual ryegrass because it has such a matted root system, and it doesn't work well in our area," he says.
The lower end of the seeding range would be 40 to 50 pounds of seed per acre if the seed is being harrowed in, he notes. "We have one grower who's getting by with 30 pounds of seed per acre. He's putting it in with a drill and getting a good, uniform stand."
With several years of strip-tillage experience under his belt, Griswold goes with a higher seeding rate for his cover crop - about 60 to 100 pounds per acre, all harrowed in.
"I went with a thick seeding rate in my first year of strip-tillage, and it proved to be a problem. We had rye standing about three feet tall, and we waited until April 15 or 20 to kill. We still were trying to work it down with a strip-till rig on about May 10, but we were turning up boulders because it was so dry.
"We had to wait for a rain, which came during the last week in May. By then, the rye was laying down and we ended up with a good cotton crop. But we learned from that experience, and we dropped back on our seeding rate. We halved the seeding rate and then gradually increased it to where it is now. Once we learned to manage it, we preferred the higher seeding rate."
A higher seeding rate for the cover crop eventually will translate into more benefits, he says. "We get better protection from wind and water erosion with a thicker cover. Weed pressure also is reduced. Increased organic matter and a better moisture-holding capacity also are characteristic of a thick cover crop."
Griswold likes to burn down his cover crop early, about 45 days ahead of planting. The thicker the cover crop, the earlier he wants to burn it down. He runs a KMC strip-till rig at least two weeks ahead of planting.
"We want to have everything killed by at least two weeks ahead of planting. Hopefully, we'll get a rain ahead of planting to help with the seed-to-soil contact. After planting, we follow our normal cultural practices."
For peanut production, Griswold hasn't made any changes in digging and harvesting the crop. "We've even planted peanuts into cotton stubble. We've had a few cotton stalks that make it through the combine and into the wagon, but the dockage wasn't too bad."
Time and labor savings are obvious benefits of growing peanuts in conservation-tillage systems, but reducing the incidence of tomato spotted wilt virus is the driving force behind current reduced-tillage research, says John Baldwin, University of Georgia Extension peanut specialist.
"Previous research has shown that we're getting less tomato spotted wilt virus under reduced-tillage systems, with or without cover crops," said Baldwin at the Southern Peanut Growers Conference. "We planted into cotton residue and corn stubble, and we planted in wheat, oat and rye covers. In all cases, we got a reduction in tomato spotted wilt virus over conventional-tillage peanuts."
In 1998, conservation-tillage was added as a factor in the University of Georgia Tomato Spotted Wilt Virus Risk Index, he adds.
Recent research, notes Baldwin, shows significant yield increases in twin-row peanuts versus single-row peanuts. "So our challenge now is to make twin rows work with strip-tillage. Twin rows almost always give us yield increases but reduced-tillage has not. We're doing the same things over and over, in different locations and in different environments, but we're not getting the same yield results," says the agronomist.
"The keys are varieties, planting date and trying to see if we can move that planting date back to April. It may be a less desirable planting date from a tomato spotted wilt virus standpoint, but we can do the other things we know will help reduce the virus and improve yield and quality - this is one of our objectives," says the agronomist.
When planting in a reduced or conservation-tillage system, growers must get a uniform stand of peanuts, says Baldwin. Current research, he says, is looking at conventional-tillage, strip-tillage and planting with a Para-till in single and twin rows.
"In strip-tillage, we find fewer lesser cornstalk borers. We seeing this on a consistent basis. This is a plus because lesser cornstalk borers are part of our aflatoxin problem in peanuts. This doesn't mean we won't have to treat for the pest, but it's less of a problem."
Research from the past four years shows less incidence of tomato spotted wilt virus in strip-till peanuts, he says. "Water conservation also is a plus in strip-tillage. Reduced-tillage will delay the wilting of a crop because you have better water retention capacity, especially in sloping fields."
Rotation, notes Baldwin, is equally important in both reduced-tillage and conventional systems. "In addition to having a good stand, it's also essential in reduced-tillage peanuts that we have our center pivots calibrated correctly. Getting everything just right is even more important in reduced-tillage."