The introduction of genetically modified, herbicide-tolerant crops has created a dire situation in the U.S. south - as weeds become more herbicide-resistant, farmers trying to maintain their 10,000-acre-plus "megafarms" are forced to apply increasing amounts of weedkiller. According to Tom Philpott and others, this pesticide treadmill is beginning to break down. Nine strains of amaranth (a.k.a. pigweed) have been labeled as noxious weeds in the U.S. One variety in particular, Palmer amaranth, has become resistant to glyphosate, the active ingredient in Monsanto's flagship herbicide Roundup. Amaranth and other so-called "superweeds" have thrown a wrench in the machine of industrial agriculture. Pigweed is sturdy enough to "stop a combine in its tracks" and reduce yields by up to 68%, which is forcing many farmers to abandon chemical weedkillers in favor of mechanical cultivators and hand weeding. The situation is so bad in Macon County, George, that 10,000 acres of farmland were deserted. The qualities that make amaranth a particularly pesky weed are the same ones reasons it has been cultivated as a food source by Indigenous peoples in the Americas since 3400 BC: it is prolific (producing up to 10,000 seeds at a time), drought resistant, reaches maturity quickly, and has an extended period of germination. It is also exceptionally nutritious; containing 30% more protein than other cereals and, like other native grains such as quinoa, it is a complete protein. The Aztecs used it as a food staple but when the Spanish priests discovered that they were also using it in religious ceremonies, they banned the sale, consumption, and cultivation of amaranth. The plant has outlasted the Spanish, bested Roundup and is being reintroduced in many places throughout Mesoamerica as an inexpensive, healthy, localized solution to hunger problems.
In response to its current superweed crisis, Monsanto blames farmers for the overuse of glyphosate, and recommends mixing glyphosate with older herbicides like 2-4,D, one of the active ingredients in Agent Orange. They are right about the overuse part -- in the ten years after "Roundup Ready" crops were introduced, glyphosate use went from 7.9 million pounds per year to 119 million pounds per year. And as for mixing glyphosate and 2-4D? Monsanto appears to have anticipated the superweed dilemma, as they patented that combination in 2001. http://www.rodaleinstitute.org/20090625/nf1