Stopping the Spread of the Hemlock Woolly Adelgid

EarthzineDEVELOP Summer 2013 VPS, DEVELOP Virtual Poster Session, Original

Vegetation decline (red) and growth (green) within the Great Smoky Mountains National Park. The change detection utilized Landsat 5 TM images acquired Nov. 10, 2001, and Nov. 24, 2006.

Team Location: University of Georgia, Athens, Georgia; and Marshall Space Flight Center (MSFC), Huntsville, Alabama


Erica Lauren Craft (University of Alabama Huntsville)

Jiaying He (University of Georgia)

Xiyu Li (Clark University)

Pornampai Narenpitak (University of Wisconsin-Madison)

Austin Stanforth (Indiana University Indianapolis)


Jeffrey Luvall, Ph.D. (NASA, Global Hydrology and Climate Center)

Marguerite Madden, Ph.D. (University of Georgia)

Steve Padgett-Vasquez (University of Georgia)

Past/Other Contributors:

Howard Neufeld, Ph.D. (Appalachian State University)

Robert Teskey, Ph.D. (University of Georgia)

Auryn Baruch (University of Georgia)

Ning Chen (University of Georgia)


The eastern hemlock (Tsuga canadensis L.) provides a unique microhabitat within the Great Smoky Mountains National Park (GRSM) for many rare and endangered species of flora and fauna.åÊ The invasion of the exotic hemlock woolly adelgid (HWA) in 2002 has critically reduced the quantity of hemlock groves within the park.åÊ With no natural predator, HWA quickly spread through the forest and has decimated the hemlock population, even old-growth stands.åÊ To combat the infestation, park managers require quick methods of tracking infestation migration and identifying locations for optimal mitigation procedures.åÊ The use of remote-sensing techniques can provide such resources.åÊ Imagery from the Landsat satellite series was collected over the infestation period, and change detection calculations of vegetation indices between years provided an infestation migration map and helped quantify the HWA’s impact.åÊ The change detection was then compared to auxiliary data to conduct regression analysis on other factors (e.g., air quality and elevation) which may contribute to the hemlock’s susceptibility to the infestation.

Return to the Summer 2013 VPS page.