Palmer amaranth above (IMAGE) Colorado State University Caption The fast growing, chemical herbicide resistant Palmer amaranth. Credit: Phil Westra, Colorado State University Credit Please credit Phil Westra, Colorado State University Usage Restrictions Please credit Phil Westra, Colorado State University License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.