A detailed look at the forest wrecking caterpillars behind an emergency eradication campaign. Then a broad overview of efforts to stop invasive threats of all shapes and sizes, from plants that can cause serious sunburns to mussels that create a razor sharp blanket of shells. Q&A with Sven Spichiger, Pest Program Manager, Plant Protection Division, Washington State Department of Agriculture & Stephanie Helms, Executive Coordinator for the Washington State Invasive Species Council.