Phytoliths from Palm Tree (image) University of Washington Caption Phytoliths, these two from a palm tree, are microscopic bits of silica that that are all that remain of plant tissue once the plant dies and decays. Phytoliths can remain in soils for millions of years as a record of what kind of plants grew at a site. Credit U of Washington Usage Restrictions Credit required 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.