In the April 2019 edition of CropLife magazine, we take our annual look at the ongoing problem of herbicide-resistant weeds. Since the first of these began appearing back at the start of the 21st century, hundreds more have shown across crop fields in America and around the globe. And the weeds continue to evolve to be resistant to newer modes of action to this day (with Class 15 herbicide-resistant varieties now confirmed in a pair of Midwestern states).
As more and more crop protection products lose their effectiveness against certain weed species, I’ve oftentimes teased industry friends that agriculture should “take a page from the Vietnam War” and “use napalm in the field” to kill weeds. “Resistance to fire is something I don’t think weeds could develop,” I’ve kidded.
Of course, now, it seems as if fire (and maybe electricity) could be in play for some growers to combat herbicide-resistant weeds. Some months ago, a co-worker sent me a YouTube video showing a modified tractor running through a spring field with an attachment sporting flamethrowers. This was running through a field burning any early sprouting weeds (and leftover seeds, according to commentary) before planting took place. Obviously, this could bring a whole new meaning to the term “burndown.”
And then, while working on the resistant weeds story for the magazine, I mentioned this video to an industry friend of mine, James Whitehead at Helm Agro. “That’s nothing,” said Whitehead. “I know of another kind of weed control that uses electricity.”
He then shared with me an item about something called a “Lightning Weeder.” According to the information Whitehead sent me (which was originally published back in the 1980s), the Lightning Weeder attached to a back of a tractor and used high voltage electricity “to immediately evaporate the water in the plant, thus rupturing cell walls within the plant, causing it to wilt and die.” At times, stated the information, certain succulent weeds could “explode on contact with the boom.”
It will be interesting to see just how widespread these alternative methods of weed control actually become in the agricultural marketplace. But I’m certain many of my ag retailer friends and their grower-customers would “just love the smell of burning Palmer amaranth in the morning!”