In growing crops, much hinges on what happens down under — as in the soil. A McLeod County farmer is taking it a step further, exploring solutions from Down Under — as in Australia.
Ryan Mackenthun operates a 2,200-acre corn and soybean farm with his brother-in-law, Nathan Zellmann. There, they’re piloting a new method of destroying weeds called harvest-time weed seed control, which relies on a rotating mill attached to the combine that separates weed seeds from harvested crops. The mill pulverizes weed seeds to the point where they no longer pose a threat to fields.
“Being in the next generation of farmers, if you’re not looking for new ways of doing things, you shouldn’t expect different results,” says Mackenthun. “Working with the University of Minnesota is an opportunity I couldn’t pass up.”
Taylor Herbert, University of Minnesota Extension educator, serves McLeod, Meeker and Wright counties. Herbert and Debalin Sarangi, Extension weed scientist, approached Mackenthun with the idea of participating in a 15-state trial to test harvest-time weed seed control.
More Critical Than Ever
Many weeds have grown resistant to the herbicides that once managed them. Mature weeds annually produce as many as half a million seeds per plant, enough to overtake a field.
“Alarming things are going on for corn, soybean and sugarbeet growers,” says Sarangi. “My goal is not to scare people but to show them this is happening. Now, what do we do? That’s what we are talking about.”
Solutions are rooted in management diversity, he notes, integrating strategies such as crop rotation, herbicide, tillage methods and cover crops. Mackenthun also participates in cover crops research.
Same Problems, Different Hemispheres
Harvest-time weed seed control was pioneered by an Australian farmer who faces the same challenges as peers worldwide. He joined forces with private industry and a crop scientist at the University of Western Australia.
“If we didn’t have that combination of the scientists, the engineers and the farmers, we wouldn’t be where we are,” says farmer-inventor Ray Harrington in a video posted by Getting Rid of Weeds (GROW), a national consortium that includes the University of Minnesota.
There are knots to work out. The mill is loud. It cannot be turned off as the combine covers weed-free parts of fields without getting out of the cab, slowing down harvest. But it has controlled weeds in Mackenthun’s fields and could help organic crop farmers, too.
“A weed’s job is to produce more weeds and they are very good at it,” says Greg Dahl, the president of the American Weed Society who has spent his career innovating management options. “We need to find all kinds of technology, stay on top of it, and never get complacent.”
“The use of mechanical seed control is likely to evolve as farmers, scientists and the ag industry take on its challenges,” says Sarangi. “After all, innovation is a series of starting points, not just finishing lines.”