By Carey Gillam
Reuters

Farmer Mark Nelson bends down and yanks a four-foot-tall weed from his northeast Kansas soybean field. The “waterhemp” towers above his beans, sucking up the soil moisture and nutrients his beans need to grow well and reducing the ultimate yield. As he crumples the flowering end of the weed in his hand, Nelson grimaces.

“When we harvest this field, these waterhemp seeds will spread all over kingdom come,” he said.

Nelson’s struggle to control crop-choking weeds is being repeated all over America’s farmland. An estimated 11 million acres are infested with “super weeds,” some of which grow several inches in a day and defy even multiple dousings of the world’s top-selling herbicide, Roundup, whose active ingredient is glyphosate.

Read the Full Article Here: http://www.reuters.com/article/2011/09/19/us-monsanto-superweeds-idUSTRE78I4BA20110919