Ponderosa Pine Forest (IMAGE) University of Washington Caption A representative photo of one of the six forest types highlighted in this study: A ponderosa pine forest, which is widespread in semi-arid landscapes in western North America. Credit University of Washington Usage Restrictions Photo credit required. 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.