The closing wheels were evaluated with replicated 50' stand counts that were taken every 48 hours after first emergence.
Three-year study examines closing wheel designs
To answer questions about the options available for closing systems, Farm Journal Field Agronomist Ken Ferrie organized a multiyear test plot to look at the various planter closing wheel designs.
"One reason why there are so many options available is that farmers are planting into a variety of seedbed conditions," Ferrie says. "The field conditions are what drive the type of closing system for your planter."
Today, Ferrie groups the closing systems into the following three categories: solid wheels, spiked wheels and firming spiked wheels.
"The purpose of the closing wheel system is to crush the sidewall, close the furrow from the bottom up and firm the soil over the seed to prevent it from drying out," he says. "Solid rubber closing wheels are designed to do this in conventional tillage. As farmers transition to reduced tillage or no-till, the rubber wheel will come up short, and the slot is left open, which is a disaster for corn stands. We have to focus on closing the slot."
To gain in-field experience, Ferrie outfitted an 8-row Kinze planter with several closing system combinations. The center four rows had solid rubber wheels on two rows and solid cast wheels on two rows. The outer two rows on each side had the following closing wheels: Copperhead Furrow Cruiser; Exapta Thompson; Great Plains Spider; Martin Spader; Pro-Stitch; Schaffert Mohawk; S.I. Distributing Close-N-Till; S.I. Distributing Finger-Till; Yetter Close-Till; Yetter Cast Spike; and Yetter Paddle.
The alternative wheels to the solid rubber and solid cast are primarily designed for tough conditions to condition the sidewall and adequately close the furrow. To understand how the wheels perform in a range of conditions, Ferrie included varying seedbeds in the three-year study ranging from no-till sod to vertical tillage with a spring harrow pass.
"In a conventional seedbed, the primary concern is that the soil will dry out, causing poor germination or poor crown root development, which sets us up for rootless corn," Ferrie says.
"Alternatively, in no-till it’s harder to get the slot closed above the seed. For example, the rubber tire does a good job of firming in conventional tillage, but it will have trouble crushing and closing the sidewall from the bottom up in no-till."
Unlike other Farm Journal Test Plots, this effort was not evaluated based on yield results. Instead 50' stand counts were taken at first emergence and every 48 hours until the counts didn’t continue to increase. The stand counts were located in multiple management zones of the field for each closing wheel.
"We know it’s important for a field to emerge uniformly, to establish photocopy plants, which leads to photocopy ears, which leads to more yield," Ferrie says. "To that effect the closing system has the job of securely closing the furrow and eliminating air pockets to improve the chance of even emergence."
The right one. The closing wheel designs are categorized by the type of action they provide. Solid wheels pinch the furrow closed from the bottom up. Spiked wheels are designed to crush the sidewall. The firming spiked wheels are designed to provide both crushing action of the sidewall and firming above the seed.
"One challenge with the spiked wheels is that on their way out of the furrow, they can bring soil with them," Ferrie says. "But our study will tell you that straight tines do a better job of crushing the sidewall then curved tines or solid wheels in the tough planting conditions like wet no-till or sod fields."
At the end of the three years, Ferrie concluded that in the tougher conditions the solid cast iron wheels in a staggered position were tough to beat. In the more mellow conditions, the solid rubber wheels performed well. However, in the toughest no-till conditions there were times the solid cast wheels did not close the slot and it was a disaster. That is where the alternative styles can get the job done better.
Ferrie also paired spiked wheels with a solid wheel on a single row.
"If I were in the field and not getting the closure I needed with two solid cast wheels, I’d make the lead wheel on each row a spiked wheel. If that didn’t provide good closure I’d switch to two spiked wheels," he says.
Needed wheel accessories. As part of the closing system test plot, Ferrie also included several add-ons—a drag chain, the Yetter firming wheel and the Exapta wedge.
"I advocate for farmers to consider dragging a chain behind their closing system. It will eliminate air pockets, and we saw that wherever we added the chain, we improved our uniform-ity," Ferrie says. "The one thing to be mindful of is to have the proper distance behind the spiked wheel closing system so that is doesn’t flip back and catch the closing wheels."
Another add-on to the closing system Ferrie tested was the Yetter Firming wheel.
"In an ideal world, farmers would change out their closing systems according to the field, but that would take more time and resources than the average farmer would give," Ferrie says. "We’ve found that this firming wheel can make a more universal fit for the spiked or firming spiked wheels when they are too aggressive for the environment. Unlike the chain, it firms the soil over the furrow."
The firming wheel reduces the air pockets around the seed while also firming the furrow.
To make a wheel more aggressive in its pitch relative to the furrow, the Exapta wedge can be added to the wheel’s bolt.
"These wedges can be set to make the closing of the slot and the crushing of the side wall more aggressive," Ferrie explains. "But they won’t help to firm the soil."
One piece of equipment Ferrie says farmers should consider including with their closing system is a seed firmer.
"It helps get the seed securely at the bottom of the furrow and into moisture," he says. "This is definitely important for even emergence."
For each farmer, Ferrie emphasizes that it is necessary for them to evaluate the job their closing wheels are doing to securely close the furrow around the seed.
"Get off the planter, do a cross section of the furrow and see how well you are doing," Ferrie says.
"Then if you are having problems crushing the sidewall, closing the slot or eliminating air pockets, use the tools available on the market to ensure the furrow closes," he adds.
Thank You to Our Test Plot Partners
Thanks go to: Copperhead Ag Products and Jake Jass; Exapta and Matt Hagny; Great Plains Manufacturing, Tom Evans and Doug Jennings; Martin Industries, John Martin and Ronnie Hoult; Pro-Stitch and Kevin Glanz; Schaffert Manufacturing and Paul Schaffert; S.I. Distributing and Dave Burgei; Yetter Manufacturing, Pat Whalen and Scott Cale; Kinze Manufacturing, Susanne Veatch and Luc van Herle; AGCO, David Webster, Luke Olsen, Reid Hamre and Lindsey Pettyjohn; Kuhns Equipment and Roger Mishler; Bob Kuntz; Rod Wilson; Bob Doenitz; Dale and Marty Traxler; Crop-Tech Consulting, Brad Beutke, Isaac Ferrie, Ethan Heidenreich, Jason Keinast, Justin Zeeb and Zach Ferrie.
You can e-mail Margy Fischer at firstname.lastname@example.org.
- Mid February 2013