Study Species (IMAGE) Frontiers Caption Pictured here: Ponderosa pine, Pinus ponderosa, and Douglas fir, Pseudotsuga menziesii Credit The authors Usage Restrictions Credit authors 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.