Conservation tillage — primarily no-till, ridge-till and strip-till — has a bevy of benefits. It saves soil, money, time and equipment, and is generally equal in yield to full-width tillage. Yet many farmers are still not convinced.
“Adoption of these systems has been slow, at best,” says George Rehm, University of Minnesota (U of M) soil scientist.
Conservation tillage may even be losing ground, both literally and figuratively, in some areas, according to experts.
“We're now actually seeing more aggressive tillage — leaving less surface residue — than we did 10 years ago in many fields,” points out Gyles Randall, another U of M soil scientist. “Tillage equipment is being pulled deeper and faster, which buries more residue, especially if there are disks on the implement.”
Precious topsoil erodes, he adds. And continued erosion could lead to stiff government regulations, agronomists warn.
But are farmers' reservations about conservation-till valid? Rehm and Alan Madison, a ridge-, strip- and no-tiller, were asked by this magazine to respond to growers' conservation-till questions.
When spring soils are cool and wet, yields can be lower with no-till corn — although still as profitable, Rehm notes. With the recent warm, dry springs, however, no-till corn yields have been fully competitive. Ridge-till and strip-till yields, he adds, are comparable to full-width tillage regardless of planting-time soil temperature.
In a 2001 Minnesota comparison involving several growers, ridge-till corn yields were 149 bu/acre vs. 145 bu/acre for conventional tillage on similar-size farms. Ridge-till soybeans averaged 44 bu/acre compared to 42 bu/acre for conventional on the same farms. What's more, production costs were 42¢/bu less for ridge-till corn and 44¢/bu less for ridge-till soybeans than for conventional.
Madison, of Princeton, IL, posted yields of 209 bu/acre with no-till corn, 215 bu/acre with strip-till corn (corn after corn) and 65 bu/acre with no-till soybeans last year. In fact, his yields were well above county averages, estimated at 165 bu/acre for corn and 47 bu/acre for soybeans. His cost per bushel was $1.70 for no-till corn, $1.73 for strip-till corn and $4.85 for no-till soybeans. That includes all costs.
By using no-till and strip-till, Madison spends less on equipment, fuel and labor. He saves the equivalent in labor of nearly one full-time employee, based on his operation's size.
“We have no-till, ridge-till and strip-till farmers using 16- and 24-row planters with no problems,” says Rehm. “You no longer need special planters, just an attachment to clear residue for no-till.”
Madison uses a 12-row planter for his no-till and strip-till acres. He could go to 16 rows, but would need a bigger tractor. “We have many no-till/strip-till farmers in this area using 16-row planters,” he adds.
If you ridge- or strip-till, you need to be the one to plant to stay on the row. That's probably true, Rehm says. “But the high-yield guys run the planter themselves, regardless of the system.”
Madison says planting on strips isn't a cakewalk but can be done. “Since you don't use planter markers, it can be a challenge when darkness sets in — unless you are on cornstalk ground, where strips show up better,” he points out.
“Actually, the longer you're on no-till, the less compaction there is,” Madison says. “Some farmers may be disappointed with no-till soybean yields, but that likely is due more to soybean cyst nematode or diseases than to the tillage system.”
If you've been worrying about having time to cultivate with ridge-till, stop. Do you grow Roundup Ready soybeans in a corn-soybean rotation? Then you only need to cultivate once every two years, Rehm notes, to build a ridge when corn is 8" to knee high. What's more, new cultivators are large 8- to 16-row units, and don't sway. Pre- and postemergence herbicides control weeds in corn.
In the past, there were potassium deficiencies when fertilizer was broadcast and not incorporated, says Rehm, “But we've solved that by deep banding. Young corn plants use the fertilizer effectively and no starter is needed. That also means rates can be reduced, saving money.”
Speaking of money, Rehm leaves this parting thought: “We have a ridge-till conference every winter, and the long-term ridge-tillers always tell us they're making money.”