Paper Development (IMAGE) Heidelberg University Caption This is a picture of two cell clones (in green), each of which originated from a single cambium stem cell and contributed to both the xylem and the phloem. Credit Dongbo Shi Usage Restrictions The material may be used only in connection with the contents of this press release, and the source of the image may also be cited. 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.