Injured Plants Warn Neighbors of Danger (IMAGE) University of Delaware Caption In experiments, a University of Delaware researcher and a high school student found that when mustard weed gets injured, it sends warnings to its neighboring plants. 'The communication signals are in the form of airborne chemicals released mainly from the leaves,' botanist Harsh Bais said. Credit Photo by Kathy F. Atkinson/ University of Delaware Usage Restrictions Must credit Kathy F. Atkinson/ University of Delaware 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.