Bullard Spotlight: Crystal Schaaf on Visualizing Hemlock Loss

2017-2018 Bullard Fellow Crystal Schaaf, a Professor in the School for the Environment at the University of Massachusetts Boston, spent her sabbatical year at Harvard Forest documenting the changes in forest structure that are occurring due to the widespread hemlock woolly adelgid (HWA) infestation of eastern forests. Professor Schaaf and her team employ satellite imagery and terrestrial lidar scans of a forest to map structural change and assess forest health.

While satellite and airborne observations of a forest provide landscape-scale information about the upper canopy, lidar scans from under the canopy provide crucial information on the pest-induced dieback of hemlock needles and branches. Lidar may also be able to capture the regrowth of understory deciduous saplings as they respond to the additional light filtering through the thinning upper canopy.

"By living onsite, we had a wonderful base of operations to store our lidars and field equipment, gain immediate access to Harvard Forest, and collaborate with an amazing group of researchers," says Schaaf. The data she and her team collected will be used for a doctoral dissertation (UMass Boston graduate student Peter Boucher) and a number of journal articles.

At the start of her fellowship at the Forest, Professor Schaaf also co-hosted a large international workshop on the use of terrestrial scanning lidars to assess forest biomass.

• Explore the Schaaf lab's remote sensing projects via a UMass Boston news feature and the lab's website
• Learn more about Harvard Bullard Fellowships

(Lidar scan image of an adelgid-infested hemlock stand, courtesy of Crystal Schaaf)