If Clare Kurz, farmer at Palmer, NE, isn’t building or modifying something, he’s probably thinking about it.

The ideas abound, small and big: from foam-filled planter tires that eliminate stalk-puncture problems as they roll over stalk stubble in his strip-tillage, to special wagons he built for hauling grain, to the computerized grain-handling system featured in a farm magazine article several years ago. It includes a 140-ft. elevator leg that he designed and built.

Even machinery he buys new isn’t immune to modification in his well-equipped farm shop. So, it’s not surprising that when he decided eight years ago to begin planting corn and soybeans in twin rows, he modified the factory-built planter he bought for planting 8-in. twin rows on 36-in. centers.

He thought about building his own planter. “But if it didn’t work out, I had an ‘orphan,’ ” he explains. So he bought a planter built by Monosem, which the company assured him he could sell if the twin-row concept didn’t pan out for him.

A modification soon followed. He replaced the originally equipped parallel linkage on the planter row units with 2-in. gas-filled racing shock absorbers enclosed within coil springs. They’re now available as an option
on the company’s planters for which Kurz now serves as a representative.

That modification takesmuch of the bounce out of planter row units, an important consideration when planting at speeds near 7 mph. The bounce or rebound resulting from the down pressure required to cut through crop residues can lead to uneven planting depth, Kurz says. The shocks with coil springs provide the necessary down pressure while dampening the bounce for uniform planting depth. Excessive row-unit bounce disturbs seed travel through planter drop tubes, upsetting seed spacing uniformity. Minimizing that agitation improves seed-spacing uniformity, Kurz points out.

Kurz has incorporated other interesting ideas into his twin-row production. But first a summary of his system and why he’s gone this route that achieves irrigated yield averages of 200-plus-bu./acre corn and 70-bu./acre soybeans.

Why twin rows?

He chose twin rows on 36-in. centers at 34,000 plants/acre over single rows on 30-in. centers at 29,000 plants/acre.

Twin-row planting allows better plant distribution and earlier canopying over the row than is possible with single rows on 30-in. centers, he believes. His system includes strip-tillage ahead of planting to reduce rainfall runoff and evaporative losses. “I feel we’re growing better corn, because we’re getting less
runoff,” he says. That and reduced moisture evaporation from the earlier crop canopying in twin rows are especially important on the sandy soils on his farm, according to Kurz.

With this type of program, he says, a fungicide treatment is important, because of the crop residue on the soil surface. “The big disease for us is gray leaf spot,” he adds.

His twin-row patternat 34,000 plants results in an 11-in. plant spacing within the row. He strives for seed spacing that is staggered in one row with the seed spacing in the opposite twin row. That pattern minimizes root-ball overlap across the 8-in. spacing between the twin rows, as well as between plants within the row.

Kurz plants mostly 113-day corn, with some 100- to 108-day hybrids. Most of his twin-row soybeans are early Group 3 planted at 160,000 seeds/acre.

He strip-tills and plants his twin rows in the row middles of the previous crop on his pivot-irrigated and non-irrigated fields. “We’re planting around the trash, rather than through it,” he says.

On gravity-irrigated fields, however, he ridge-tills, planting in the previous twin-crop row area on the ridges to preserve the irrigation furrows in between.

In this sandy soil area where groundwater quality protection regulations restrict nitrogen (N) application timing, he applies some of his N as anhydrous ammonia with his strip-till pass in the spring. He applies 10-34-0 solution and thiosulfate with the strip-tillage pass about 10 days ahead of planting. Each row unit on his strip-tillage machine includes row cleaners, a coulter ahead of a chisel running about 9 in. deep (for anhydrous ammonia application), wavy coulters slightly angled to pull soil back over the chisel slot and rolling baskets.

He also applies fertilizer as in-row applications of 8-25-0, 28% N solution and sulfur with the planting operation. Kurz does this whether planting in the old rows in ridge-till or in the row middles under pivot irrigation. The balance of N goes on through a center pivot or sidedressed with a coulter machine.

Stalk stubble vs. tractor tires

Problems with stalkstubble chewing up tires on the planter tractor led to another of Kurz’s shop projects. To remedy the problem, Kurz built and mounted 13-in.-diameter rollers at the front of his tractor to flatten stalk stubble ahead of the tractor tires. He designed the hydraulically raised rollers to float up and down with undulations in the field surface. Without the stalk flattening, he says, “you won’t even make it through the day (without damage to the tires).”

He first tried rolling stalk cutters ahead of the tractor tires. Vibration created by the stalk cutters prompted him to abandon them in favor of the rollers.

Kurz follows a cropping sequence of three years in corn followed by one year in soybeans, so most of his corn planting is into cornstalk stubble.

“I try to rotate my herbicide program,” he says, to avoid depending solely on glyphosate. Corn planted the first year after beans is a non-GMO hybrid with an application of Callisto. Second-year corn is Roundup Ready and third-year corn is either Roundup Ready or a glufosinate-ammonium product (Liberty or Ignite), in conjunction with a pre-emerge/preplant herbicide. He returns to soybeans the fourth year with a Roundup Ready soybean variety.

All of his corn and soybeans were planted by May 1 this year. “I work more off the calendar than (soil) temperature,” he says, explaining that he shoots for the middle of April to begin planting.

He keeps two 24-row (12-twin-row) planters rolling with a seed caddy that he modified to fill planter boxes from any of the four bulk seed containers on the caddy. With a crank on a chain and sprocket assembly, he moves the hopper under the bulk seed containers from one bulk container to another. Forced air moves seed through a flex tube running from the hopper to the planter boxes.

His latest experiment with strip-tillage and twin rows is planting rye in the fall to protect sandy soil against wind erosion over the winter.

He strip-tilled this spring and planted Roundup Ready corn into the growing rye, before applying Roundup to kill the rye following planting. He ended up having to make a second Roundup application to completely kill the rye.

November 2010