Strip-tilled corn may get lots of attention, but Webster City, Iowa, strip-tiller Arlo Van Diest also likes using the practice for soybeans.
Van Diest has been strip-tilling since 2002 and has strip-tilled 100% of his corn and soybean ground since 2004. He raises all of his soybeans for seed for Pioneer Hi-Bred.
Since Van Diest lives right on the highway, his strip-tilled fields are very visible and he gets many questions about the practice. Van Diest promotes strip-till to other farmers in the area and he's also hosted strip-till field days on his farm.
He says strip-till helps him build a better seedbed, manage compaction and save money on inputs.
A Better Seedbed
Van Diest likes to strip-till in the spring because it produces a better seedbed for soybeans and continuous corn.
"It moves the residue to the side and warms quickly," he says. "After strip-tilling for a few years the field becomes noticeably mellow. You can put a 3/4-inch rod down the seed slot any time of the year and that's important.
"Surface water drops more quickly," he adds, "and you will also notice that soybeans are a tap root plant. In conventional tillage, soybean roots go down about 4 inches and then hit compaction and the roots turn and grow horizontally."
Van Diest uses a 16-row, John Deere 1770 planter with 30-inch spacings for no-tilling corn and soybeans. He added trash whippers and sets them so they just skim the surface of the soil and move clods out of the way.
"I don't want the trash whippers set so low they dig a hole in the seedbed," he says.
Strip-tilling enables Van Diest to manage seed populations for corn and soybeans.
He doesn't need to increase the corn-plant population to compensate for kernels that would not germinate due to poor seed-to-soil contact.
"By strip-tilling continuous corn, we don't have any corn cobs or root balls where we plant," Van Diest says. "There's good seed-to-soil contact."
He plants 34,500 kernels per acre for both continuous corn and corn following soybeans, and plants 120,000 to 130,000 soybeans per acre.
Van Diest strip-tills with a 16-row DMI fertilizer applicator bar with 30-inch centers. Each row has a shank with a mole knife, but they aren't very aggressive. For both soybeans and corn, Van Diest runs the knife 8 to 12 inches deep.
"I think the mole knife allows room for the anhydrous ammonia, and with good depth we have not had any plant burn from anhydrous ammonia," he says.
In the fall, Van Diest strip-tills and applies anhydrous ammonia on the soybean ground that he will no-till to corn in the spring.
"It may be better to apply anhydrous ammonia in the spring, but we like to spread the workload and anhydrous ammonia is lower priced in the fall," he says.
In the spring, he strip-tills cornstalks in fields he plants to soybeans. He doesn't put down any fertilizer for the soybeans.
Diest also strip-tills continuous-corn acres in the spring, applying anhydrous ammonia. For corn, Van Diest broadcasts potash and phosphate as needed, based on the results of soil testing from 4 acre grid samples.
"I think we have enough residue on the surface that we don't have to worry about phosphorus and potash running off the fields and into the tile lines," he says.
Van Diest says his farm is "kind of fussy" about compaction and he's convinced that strip-till helps him manage it.
"We try to avoid using catch wagons when we are harvesting," Van Diest says.
"We harvest 2,300 acres with a two-man operation, and have our own storage, so our harvesting isn't tied to the delivery hours at the grain elevator. We like to have only one trail for the semi across the middle of the field, which we park at right angles to the direction we planted.
"We combine back and forth across the field — at right angles to the direction we planted — and empty the combine in the middle of the field into a parked semi truck. The only time we use a catch wagon is when we have too much corn to get to the semi. Then we offset the middle of the field and park the catch wagon at the ends of the longer rows and unload only enough to get back to the semi."
Economics A Factor
A major factor in his choice to go to strip-till was economics.
"With strip-till, you have just one trip across the field before you plant," Van Diest says.
"Farmers using conventional tillage — especially for continuous corn — are making two, three or even more tillage trips before planting. With strip-till, you don't have to shred corn stalks, or disc-chisel, field-cultivate or roll fields.
"Strip-till is also very environmentally friendly compared to conventional tillage," he adds. "It reduces soil and organic matter lost to wind or water erosion, which is important because that cuts down the amount of phosphorus and potassium that moves off the fields and into the water."