Learning How a Crop Becomes a Weed (IMAGE) Washington University in St. Louis Caption Washington University in St. Louis biologist Kenneth Olsena and postdoctoral research fellow Cindy Vigueira sample weedy rice in the WUSTL greenhouse for DNA extraction and analyses. Credit Genevieve Hay Usage Restrictions None License Licensed 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.