US glyphosate resistance warning
US weed control specialists and major glyphosate suppliers are urging farmers to review their use of the herbicide following the confirmation of glyphosate-resistant populations of giant ragweed (Ambrosia trifida) in Indiana and Ohio. This is the seventh weed species to be confirmed as showing resistance to the herbicide in the US. Glyphosate-resistant ragweed has been found in three fields in Ohio and in one field in Indiana. The field of soybeans in Indiana had been treated solely with glyphosate for six out of the last seven years.