Just a few hundred miles away from Bismarck, North Dakota, a Green Menace is wreaking havoc with city trees—destroying tree-lined streets and causing property damage.

That menace is the emerald ash borer. And it made its way into St. Paul, Minnesota in early spring of 2009. Though it hasn’t been detected in nearby North Dakota, the city of Bismarck is bracing for the worst—just in case the invader makes a jump across the border.