Invader batters rural America, shrugging off herbicides : glyphosate resistance
- Invader batters rural America, shrugging off herbicides
By Michael Wines
New York Times 12 August 2014
Palmer amaranth is the most notorious of a growing number of weeds that are immune to the gold standard of herbicides, glyphosate. With a stalk up to six inches thick, it can damage farm equipment. Glyphosate-resistant palmers first surfaced in 2005, in Georgia. They are now in 24 states.
Constantly dousing crops in glyphosate has exacted a price. Weeds with glyphosate-resisting genetic mutations appeared faster and more often in 16 types of weed so far in the United States. A 2012 survey concluded that glyphosate-resistant weeds had infested enough acreage of American farmland to cover a plot nearly as big as Oregon, and that the total infestation had grown 51 percent in one year.