Wieslander Vegetation Survey Data (IMAGE) University of California - Davis Caption Data collected during the Wieslander vegetation survey in the 1920s and 1930s were used in the new climate study. Credit Marian Koshland Library, UC Berkeley 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.