Tis the season when many Americans welcome trees into their homes. For millions of us, fresh-cut evergreens are at the heart of Christmas celebrations – a symbol of hope and joy. Sadly, the situation facing America’s trees is neither hopeful nor joyous.
The scourge of forest pests is expected to put almost two thirds of America’s forests at risk by 2027, costing several billion dollars every year for dead tree removal and jeopardizing longstanding U.S. industries that rely on timber.
In a towering forest of centuries-old eastern hemlocks, it's easy to miss one of the tree's nemeses. No larger than a speck of pepper, the Hemlock woolly adelgid spends its life on the underside of needles sucking sap, eventually killing the tree.
Growing reliance on both trees and trade makes imported forest pests the most pressing, and under-appreciated, forest health issue in the US today. Five high-priority policy actions that build on proven prevention measures can reduce the arrival and establishment of new forest pests.
Hemlock is a "foundation" tree species in eastern forests and its presence defines the properties of a unique ecosystem that is presently declining due to the introduction and spread of an invasive insect, the hemlock woolly adelgid.
Earthworms effect microbial nitrogen cycling and ecosystem nitrogen retention. Earthworm invasion of north temperate forests will have large consequences for nutrient retention and uptake in these ecosystems.