After a decade of intensive genetically modified plant cultivation, weeds have emerged that are resistant to the most popular herbicide.



I was a member of the FDA Food Advisory Committee when the agency approved production of genetically modified foods in the early 1990s.

At the time, critics repeatedly warned that widespread planting of GM crops modified to resist Monsanto's weed-killer, Roundup, were highly likely to select for "superweeds" that could withstand treatment with Roundup.

I wrote about this problem in Safe Food: The Politics of Food Safety. I added this update to the 2010 edition:

Late in 2004, weeds resistant to Monsanto's herbicide Roundup began appearing in GM plantings in Georgia and soon spread to other Southern states. By 2009, more than one hundred thousand acres in Georgia were infested with Roundup-resistant pigweed. Planters were advised to apply multiple herbicides, thereby defeating the point of Roundup: to reduce chemical applications.

Today, the idea that planting of GM crops is "widespread" is an understatement.

So, according to Reuters, is Roundup resistance.

Weed resistance has spread to more than 12 million U.S. acres and primarily afflicts key agricultural areas in the U.S. Southeast and the corn and soybean growing areas of the Midwest. Many of the worst weeds, some of which grow more than six feet and can sharply reduce crop yields, have become resistant to the popular glyphosate-based weed-killer Roundup, as well as other common herbicides.

This is not a trivial problem. As the Ottawa Citizen explains,

The resilience of nature is evident across almost five million hectares of superweed-infested U.S. farmland. Some runaway weeds in the southern U.S. are said to be big enough to stop combines dead in their tracks.

How is the chemical industry responding to this threat? Zap it harder!