I’ve written a couple of times about the rise “superweeds” in the Southeast and mid-South.

In Arkansas, horseweed and Palmer amaranth now choke fields planted with Monsanto’s Roundup Ready cotton and soy — engineered to withstand heavy doses of Roundup, Monsanto’s broad-spectrum herbicide. Fifteen years ago, horseweed and amaranth weren’t problem weeds. </p

Back in March, Arkansas Agricultural Extension Service officials were pushing farmers to supplement their Roundup applications with doses of Reflex, a broad-spectrum herbicide made by Monsanto’s rival, Syngenta.

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Now the agribiz-friendly extension service is hotly promoting the wares of another Monsanto rival, Bayer Crop Sciences, Delta Farm Press reports. Bayer’s Liberty Link soybeans, designed to withstand doses of Bayer’s broad-spectrum herbicide Ignite, will be available next year.

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The active ingredient in Ignite is glufosinate ammonium — evidently pretty nasty stuff. Here is the International Pesticide Action Network:

At sub-lethal doses, glufosinate can have significant, but not so easily observable impacts. For example, a recent study found that low doses of glufosinate affected central nervous system development in young rats … The results suggested that exposure to even low doses of glufosinate in the infantile period in rats causes changes in the kainic acid receptor in the brain.

According to PAN, the EPA classifies glufosinate ammonium as “persistent” and “mobile” — meaning it sticks around and moves easily through soil and water.

Then there’s this:

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In one study, residues of glufosinate were found in spinach, radishes, wheat and carrots planted 120 days after glufosinate had been applied. In sandy soils, which overlie many aquifers, glufosinate has been found to be highly persistent due to lack of biodegradation. Its transport through the soil was also determined to be “essentially unretarded.” Glufosinate’s metabolite, MPPA-3, has been found to be more persistent and more mobile than glufosinate [itself].

It’s hard to see what good can come of this GMO/pesticide treadmill — unless, that is, you own shares in one of the very few companies that dominate the GMO/agrichemical market.