Wednesday, April 22, 2009

Super weed threatens cropland in the the southern US

That greatest of blogs, the Undernews, via France 24: A new pest, the evil pigweed, is hitting headlines and chomping its way across Sun Belt states, threatening to transform cotton and soybean plots into weed battlefields. In late 2004, "superweeds" that resisted Monsanto's iconic "Roundup" herbicide, popped up in GM crops in the county of Macon, Georgia. Monsanto, the US multinational biotech corporation, is the world's leading producer of Roundup, as well as genetically engineered seeds. Company figures show that nine out of 10 US farmers produce Roundup Ready seeds for their soybean crops.

Superweeds have since alarmingly appeared in other parts of Georgia, as well as South Carolina, North Carolina, Arkansas, Tennessee, Kentucky and Missouri, according to media reports. Roundup contains the active ingredient glyphosate, which is the most used herbicide in the USA. Today, 100,000 acres in Georgia are severely infested with pigweed and 29 counties have now confirmed resistance to glyphosate, according to weed specialist Stanley Culpepper from the University of Georgia.

"Farmers are taking this threat very seriously. It took us two years to make them understand how serious it was. But once they understood, they started taking a very aggressive approach to the weed," Culpepper told "Just to illustrate how aggressive we are, last year we hand-weeded 45% of our severely infested fields," said Culpepper, adding that the fight involved "spending a lot of money."

In 2007, 10,000 acres of land were abandoned in Macon country, the epicenter of the super weed explosion, North Carolina State University's Alan York told local media. Had Monsanto wanted to design a deadlier weed, they probably could not have done better. Resistant pigweed is the most feared superweed, alongside horseweed, ragweed and waterhemp….

I don't know whether this is a picture of the species in the article, but it's Amaranthus albus L., Prostrate Pigweed. Growing in desert wash, eastern Maricopa County, Arizona, USA. syn: A. graecizans L. Shot by Mike, Wikimedia Commons, under the Creative Commons Attribution ShareAlike 3.0 License


Andy said...

A few good sites to find weed pictures:

The Latin name of the resistant weed would be very helpful. The website is a good reference to find information on resistant weeds. I'm assuming you are referring to Palmer Amaranth ("Amaranthus palmeri") in this article, not pigweed in general. Resistant weeds are becoming a huge problem.

Brian Thomas said...

Thanks for these photo sites -- maybe I'll give my usual sources a rest.