Hemlock Extinction Looms over Tennessee Forests:

            The Hemlock trees of the Eastern United States are growing closer and closer to extinction. These huge trees, a valuable provider of habitat to hundreds of species in its ecosystem, are being killed by something much, much smaller. Both the eastern and Carolina Hemlocks suffer infiltration by the Hemlock woolly adelgid. The super small insects form a parasitic relationship with the trees, using the tree’s sap as its own food source, depleting Hemlocks of their reserves. The adelgids have been spreading and now can be found among sixteen different states. Scientists research ways to prevent the death of Hemlocks under the little bugs. Botanist Todd Crabtree has found the way of inserting the pesticide Imidacloprid into the soil around the tree, with the tree then soaking up and spreading it among itself, an effective way to ward off any ambitious woolly adelgids. With over fifty percent of the total population of Hemlocks now infected, the future looks bleak for the trees. But there is hope; and Crabtree and his colleagues will keep searching for ways to prevent the depletion of Hemlocks under the deadly insects. I believe the efforts by Crabtree truly admirable. Gigantic trees like the Hemlock that contribute so much to an ecosystem should not go extinct due to an invasive species. The Hemlock trees might survive.

http://blogs.scientificamerican.com/extinction-countdown/2013/10/11/hemlock-extinction-looms/