River Cassarate in Lugano, Switzerland (IMAGE) Pensoft Publishers Caption This image shows an invasion by knotweed at the side of the river Cassarate in Lugano, Switzerland. Credit Franziska Humair Usage Restrictions CC-BY 4.0 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.