A new study authored by the University of Montana’s Bureau of Business and Economic Research and the U.S. Forest Service Rocky Mountain Research Station examines the impact of the mountain pine beetle on costs, operations and timber product value related to harvesting, processing, transporting and sawmilling trees killed by the beetle in Montana. The study authors are BBER’s Dan Loeffler and the research station’s Nate Anderson. Over the past 15 years, the mountain pine beetle has caused considerable pine tree mortality across Montana, affecting more than 9 million acres of forest. …Loeffler and Anderson found that trees in the red or gray stage of mountain pine beetle mortality comprised about one-quarter of Montana sawmill log supply from 2010 to 2014, but dropped to 5.8 percent of sawmill log supply by 2015. …Loeffler and Anderson also found that logging, loading, hauling and sawmilling costs increase 15 to 18 percent.