For decades, the mountain pine beetle has caused an unprecedented amount of forest mortality in western North America, tearing through pine stands from the Pacific Coast all the way to the Black Hills of South Dakota.  Now, researchers at the Minnesota Invasive Terrestrial Plants and Pests Center (MITPPC) are preparing for the impending arrival of one of the top threats to Minnesota’s trees.  Brian Aukema answers questions about the species and why they pose a threat to Minnesota pine forests.  ….A warming climate, unprecedented population of beetles, and firewood and timber transport could help this destructive forest pest make its way across the prairie divide. That’s why, even though researchers have yet to find mountain pine beetle in the state, MITPPC has ranked it as the No. 1 invasive insect priority for research funding.