Researchers at Iowa State University warn that herbicide-resistant weeds
are proliferating and may jeopardize U.S. food supply.
In an article published in Journal of Agricultural and Food Chemistry,
weed scientist Michael Owen said the proliferation of superweed “has
been fairly dramatic in the last two to three years.”
Weeds are developing resistance to glyphosate, the active ingredient in
Roundup, which has been used extensively since 1996.
U.S. soybean, cotton and corn production could suffer from further
proliferation, according to
“Today, 98 percent of U.S. soybeans, 88 percent or so of U.S. cotton
and more than 70 percent of U.S. corn come from cultivars resistant
to glyphosate,” Owen reports. Reliance on these crops — and an
accompanying weed-control strategy that employs glyphosate to the
exclusion of other herbicides — “created the ‘perfect storm’ for
weeds to evolve resistance,” Owen and Jerry Green of Pioneer Hi-Bred
International in Newark, Del., argue in their new analysis.
Dr. Stanley Culpepper of UGA Tifton says 52 counties have the mutant pigweed.
He says they’re looking at cover crops and deep turning.
(You may know that as plowing.)
He hastily adds that they’re looking at other herbicides.
But he wraps up by saying we have to look at other methods
than herbicides: tillage and cover crops.
He frames it as diversity and integration.
What it really means is spraying poisons eventually
breeds weeds that refuse to be poisoned.
People, of course,
are not so lucky.
“To human cells glyphosate is already toxic in a very low dose.
A farmer uses a much higher dose on the field.
Roundup is even more toxic than glysophate,
for that is only one of the ingredients in Roundup.”
Roundup says none of this applies to humans and Roundup is safe.
Steckle said we’ve now reached the point where we have to begin thinking in terms of controlling “resistant weeds” instead of “resistant marestail” or “resistant Palmer pigweed” because they are both beginning to show up in the same field.
“We have to manage them both,” he said. “There’s a new product from BASF called Sharpen that I’ve been looking at for five years and I’ve been very impressed with the marestail control. I still like dicamba, Roundup and Gramoxone.
“But if you have Palmer pigweed, too, then you’re going to have to overlap with residuals ― Cotoran, Caparol, Prowl ― to have any chance to do a good job of controlling them.”
Deep tilling of crop land pocked and rutted by heavy equipment used on rain and snow soaked, often frozen farm land may not only clean up the land, but may have a significant positive effect on managing herbicide resistant weeds, especially
Back to the future!
“Deep tilling” is the current buzzword for plowing.
That’s how my father farmed, with a bottom plow, a subsoiler, a harrow,
The same article continues to defend no-till:
There is no doubt about the many benefits of minimum or no-till cropping systems. Reduced-tillage saves farmers money in equipment, improves soil quality, improves the environment by making the soil more porous and produces better drainage. The list of benefits goes on and on.
Promotes more erosion, is my observation.
And how does no-till save farmers money if they have to pay for increasing
amounts of pesticides to try to deal with mutant weeds like pigweed?
Continue reading →
It’s a funny thing about monocultures. They’re highly vulnerable to anything
that affects that particular variety.
Dr. Mae-Wan Ho writes:
The scene is set at harvest time in Arkansas October 2009. Grim-faced farmers and scientists speak from fields infested with giant pigweed plants that can withstand as much glyphosate herbicide as you can afford to douse on them. One farmer spent US$0.5 million in three months trying to clear the monster weeds in vain; they stop combine harvesters and break hand tools. Already, an estimated one million acres of soybean and cotton crops in Arkansas have become infested.
The palmer amaranth or palmer pigweed is the most dreaded weed. It can grow 7-8 feet tall, withstand withering heat and prolonged droughts, produce thousands of seeds and has a root system that drains nutrients away from crops. If left unchecked, it would take over a field in a year.
Meanwhile in North Carolina Perquimans County, farmer and extension worker Paul Smith has just found the offending weed in his field , and he too, will have to hire a migrant crew to remove the weed by hand.