A Battle for Our Hemlocks

Hemlock trees provide nature with shade, shelter, and beauty. They play a vital role in cooling streams and creeks to make water suitable for aquatic creatures. They are home to a diverse population of creatures throughout the Appalachian Mountains including creatures of the Great Smoky Mountain National Park. Without these trees, the Appalachian ecosystem would struggle; unfortunately, hemlock population is drastically declining due to a non-native species called the hemlock woolly adelgid (Doccola). The woolly adelgid are a tiny non-native species that feed on the starch nutrients of the hemlock tree. The adelgid gained its name from its white, wax-like outer coating that appears woolly. The adelgid gather in dense clumps, mostly at the base of the tree, and latch onto the branches of hemlocks, sucking out the nutrients necessary for the growth of the tree. Without the nutrients, the hemlocks’ branches begin to die and fall off. Within a four year period, the hemlock is dead (Doccola). The hemlock woolly adelgid was discovered in the Great Smoky Mountain National Park in 2002. Since then, the adelgid have spread throughout the park. These tiny insects continue taking down massive hemlocks measuring past 150 feet tall with bases 6 feet in diameter. Over 900 acres of old hemlocks and 8,000 acres of young hemlocks face the risk of death due to the woolly adelgid (“Hemlock”). The Hemlock Woolly Adelgid reproduce in the winter and spring and usually go dormant during the summer months (Doccola). Hemlocks spread from tree to tree by birds, wind, and mostly humans. With the increasing spread of the adelgid, more treatments are being used to attempt to save hemlocks of the east (“Hemlock”). Currently, scientists are using three methods to save hemlocks from the adelgid; however, these methods have their drawbacks and cannot reverse the damage that has already been done. The first treatment known as foliar treatment works only on hemlocks accessible from roads.

Cited: Busch, Ron. "The Hemlock Woolly Adelgid." New Life Journal Dec. 2005: 34. Student Edition. Web. 14 Dec. 2012. Childs, Gina. "Hemlock woolly adelgid." Arbor Age Feb. 2005: 10. General OneFile. Web. 16 Dec. 2012. Doccola, Joe. "Hemlock Woolly Adelgid." Arbor Age Oct. 2012: 7. General OneFile. Web. 13 Dec. 2012. "Hemlock Woolly Adelgid." National Parks Service. National Parks Service, 08 Nov. 2012. Web. 14 Dec. 2012.