Hemlock trees killed by hemlock woolly adelgid in Great Smoky Mountains National Park, North Carolina. (Courtesy Songlin Fei)

With its sparkling green wings, the emerald ash borer, a tiny beetle no longer than a knuckle-length, is almost beautiful. The insect however has been ravaging America’s forests for nearly 20 years. First seen in Michigan in the early 2000s, the invasive pest has killed millions of ash trees in more than 30 states. 

The ash borer is not the only species devastating