Strip-tillage helped one young Minnesota farmer get started in agriculture “from the ground up.”
Keith Landwehr grew up on a farm, but didn't have the option of joining the family business. So he became an accountant instead. “But I really, really wanted to farm,” he says. Determined to reach that goal, he and his wife Sheila, also an accountant, put together a long-range plan that allowed Landwehr to begin farming full time last year.
The couple started out by purchasing 200 acres of cropland in central Minnesota, near Watkins. After renting land for several years and saving for equipment, Landwehr planted his first corn crop in 2001. “It wasn't feasible for us to purchase all the equipment and horsepower for conventional tillage,” he says. “Yet, I didn't think no-till would work. We have a lot of heavy, wet, mucky soil.”
At the time, he didn't know anybody nearby who was doing strip tillage, but he'd read a lot about it and thought it made sense for his operation. So he modified a vertical tillage tool to do strip-tillage. At first, Landwehr says, his neighbors were pretty skeptical about the alternative tillage system. “But now, landlords have started to call us, asking us to rent their land. They like what they see.”
By 2005, Landwehr had expanded his farming operation to the point where he could afford to quit his job in town and farm full time. In 2006, he hired his first employee and bought a second tractor. Now, fall strip-tillage is catching on with other local corn producers, so he's doing a lot of custom strip-tillage, too.
About 95% of Landwehr's operation is continuous corn. “Soybeans are not a good crop for us here,” he says. “We've got too much iron deficiency chlorosis and soybean cyst nematode.”
Just as important, he says, “There aren't enough profitable markets for soybeans close by. But we have a lot of corn markets to choose from.” Landwehr is big on forward marketing, contracting corn three years out, “so you can guarantee profitability in future years.”
Landwehr strip-tills in the fall, banding phosphorus (P) and potassium (K) about 5 in. deep under the strips. The liquid fertilizer is injected off the back of the right coulter. His Dawn 12-row, 30-in. tillage tool clears a 10-in.-wide strip, tilling 400-450 acres a day. It saves the residue cover between the strips, which has eliminated the spring gullies that were common when the fields were chisel plowed, he says.
In the spring, Landwehr plants twin rows in the tilled strips, using a modified Kinze 3600 planter. One of the benefits of fall strip-tillage is “no waiting for field preparation in the spring. Planting is your most critical time,” he says, and strip-tillage “improves your ability to plant at the optimum time. We look for any fields that are ready, pull in and plant.”
Landwehr seeds twin rows, 7½ in. apart, on 30-in. centers, using GPS-guided steering. “The twin rows are key,” he says, “because it's more efficient to band fertilizer in two rows instead of one.”
Canopy closure is quicker, too, he says. His seeding rates range from 35,000 to 44,000 plants per acre, which gives him ⅞-in. stalks and 9- to 12-in. plant spacings within the rows. “I don't say there's a yield increase with twin rows,” he says, “but I've been happy with my yields.”
Landwehr does three nitrogen (N) applications, banding one-third at planting and another third along with his post-emergent burndown, with nitrogen as the herbicide carrier. The balance is side-dressed at the V-8 to V-10 stage. His Cat 755 tractor is equipped with two 425-gal. tanks, with spray valves mounted on the toolbar. His sprayer has a 90-ft. boom with 15-in. nozzle spacings, allowing fertilizer to be placed between and to the sides of the twin rows. On the third fertilizer pass, Landwehr turns off every other nozzle.
Landwehr says his strip-tilled corn is generally behind his neighbor's conventionally tilled corn until the end of June, or so, when it catches up. “If we get a dry spell in July, we pull ahead because we've saved our moisture. The tradeoff is that we work with wetter, colder soils in the spring, but we have that moisture in the summer,” he adds.
Immediately after harvest, Landwehr builds next year's new strips, moving the tilled zone over 15 in. into the previous year's rows. The high amount of residue from continuous corn makes it essential to lay out the strips perfectly in the fall, he says. All his field equipment is set up on single track, 120-in. spacings to accommodate a controlled traffic pattern.
Continuous corn requires high fertility. Landwehr samples all his fields every three years on 2½-acre grids. “We have highly variable soils,” he says. He applies lime, P and K at variable rates.
“The savings on lime alone pays for the cost of soil testing,” he says. He typically applies 140 lbs./acre of N, but has started experimenting with variable N application, too. Landwehr also runs plant tissue tests to monitor nutrient uptake and says, “We're getting to understand our soils very well now.”
Landwehr has used strip-tillage since he started farming six years ago, so he can't compare his yields to a conventional corn tillage system. He does have to deal with extremely heavy residue. “People look at it and say, ‘No way you're going to plant into that.’ But we do.” It takes a lot of management, though, he says. “You can cover up a lot of mistakes with tillage.”
He hasn't seen any yield drag from successive years of corn, either. “I've increased my yields every year,” and just as important, “we're improving our soil,” he says.