White pine blister rust (WPBR) is an exotic, invasive fungal disease of white, stone, and foxtail pines (also referred to as white pines or five-needle pines) in the genus Pinus and subgenus Strobus (Price and others 1998). The disease, which is native to Asia, was accidentally introduced separately into eastern and western North America at the beginning of the 20th century. In the West, WPBR was introduced on infected eastern white pine (Pinus strobus) nursery stock shipped to Vancouver, B.C., from France in 1910. Since then, the disease has spread into the distributions of most western...