A new variation on the familiar disc tackles the challenges of managing crop residues, volunteers, and weeds, while also preparing the seed bed for a crop.
“Has anyone seen a disc that looks like this before?” said Philip Korczak, holding up a steel disc with a wildly serrated edge.
Korczak, regional manager for Väderstad Industries, is presenting the company’s innovative disc to about 40 producers, agronomists, and suppliers at the Discovery Farm Fall Field Day west of Langham, Sask., on Oct. 21.
Väderstad, a Swedish tillage and seeding equipment manufacturer, is perhaps best known in the province through their acquisition of Seed Hawk in 2013.
The oddly shaped disc is the key component of the Väderstad Crosscutter, where they are set in two ranks with the leading rank offset by 14 degrees from the rear. Both are followed by a rank of heavy packers. The entire setup is mounted on a heavy carrier and pulled at 16 to 19 km/h.
Korczak explained the idea was born in Germany, where oilseed rape growers wanted a way to go over their fields post-harvest to ensure volunteers and weeds germinated, while also conserving soil moisture.
“What the solution ended up being, after three or four iterations, is what we call the crosscut disc,” Korczak said.
Conventional discs basically cut grooves in the field, turning over the soil. Not only does this leave the area between the blades relatively undisturbed, it buries weed and volunteer seeds. These get disturbed by spring seeding and germinate to compete with the crop.
In contrast, the crosscutter disc churns crop residue with the top one to three centimetres of soil, leaving volunteers and weeds to germinate and be killed by winter frost, mechanical means, or herbicide. The implement also crushes and mulches cover crops.
Incorporating crop residue may also have other benefits.
Jeff Schoenau, a professor of soil fertility and professional agrologist in the department of soil science at the University of Saskatchewan, explained during a tour at the field day that phosphorus in crop residue is highly soluble. Mulching and incorporating it may help keep it on the field for the next season.
A research project at the Discovery Farm with the Väderstad Crosscutter plans to explore this question.