Add one more state and two more weeds to the growing list of plants resistant to the popular herbicide glyphosate and states in which they're found.

Iowa State University agronomy professor Mike Owen has confirmed populations of waterhemp and giant ragweed that are resistant to the herbicide in his state.

To read the complete article, visit Syngenta Crop Protection.

For a list of all of the herbicide-resistant weeds in the United States, the states where they've een found, and the products to which which they are resistant, visit