Tree Trunk Fossil (IMAGE) Chinese Academy of Sciences Headquarters Caption This is the largest silicified trunk in the field, with a maximum diameter of ~70 cm, from the Upper Devonian of Xinjiang, Northwest China. Credit Image by XU Honghe 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.