White Spruce Core (IMAGE) University of Alaska Fairbanks Caption Sam Demientieff takes a core sample from a mature white spruce tree along the lower Yukon River in 2007. Credit Courtesy of Photo by Claire Alix Usage Restrictions University of Alaska Fairbanks Marketing and Communications makes high-resolution photographs available to the news media for non-commercial uses only. All uses are for one-time, non-exclusive use in one publication or production only. Due credit will be given to the photographer whose name is provided by UAF Marketing and Communications. Other image requests can be submitted via our online image request form at: http://www.uaf.edu/marketing/photo/image_request.html. 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.