This is an Eastern hemlock forest (Tsuga canadensis). The illustration on the left shows a healthy forest, a beautiful place to explore on a summer day, to sit quietly and listen to the vireos, and return to with your snowshoes in winter. On the right is what that forest could look like after an infestation of hemlock woolly adelgid* (Adelges tsugae). It’s a whole different environment! This highly invasive insect from Asia kills hemlock trees in just a few years, eventually destroying large patches of forests and the unique micro-climates they create.
Large, healthy hemlock trees provide shady habitat where the air and water are cool and clear. Many plants and animals thrive in this specific ecosystem, so the effects of a hemlock woolly adelgid invasion can be devastating. (Animal species associated with Eastern hemlock include trout, great horned and saw whet owls, vireos, hermit thrush, snowshoe hare, porcupine, red fox, marten, bobcat, white-tailed deer, red squirrel, and black bear.)
See the USDA’s Hemlock Woolly Adelgid Species Profile (2014) for more information and a great list of resources. The adelgid’s range is growing each year, and is of great concern in places like the Great Smokey Mountains, Pennsylvania, New York, Southern New England, and Maine, to name a few. The US Forest Service has a good map.
About the Artwork
Hemlock woolly adelgid is beginning to creep into the forests here in Upstate New York. At Huyck Preserve in Rensselaerville, NY, home to a 200-year-old hemlock forest, the scientists are working hard to educate visitors about the problem and prevent further spread. I collaborated with them to create these illustrations, part of a series that will be built into an interactive display for their visitor’s center. My process involved spending time and sketching in the Preserve’s old-growth forest, and learning about the life cycles of the trees and the insect. Below I give you a peek at my mixed media technique (pencil, watercolor, and digital).
* Adelgid is pronounced (a-DEL-jid).