Written by David Greene
Chances are that if you have been hiking the Southern Appalachians in the last few years, you’ve come across some of these shiny, orange and red mushrooms. They are Ganoderma tsugae, or the hemlock varnish shelf, and they are a sign of the changing times.
Since the introduction of the non-native Hemlock Wooly Adgelid in the 1950’s, nearly 90% of the Eastern Hemlock trees in the Appalachains have been impacted. As such, these dead or dying hemlocks are now a common sight. All of that dead wood is a welcome sight to the hemlock varnish shelf mushroom, which grows almost exclusively on dead hemlocks (some spruce and pine are also hosts).
The widespread and sudden deaths of our beloved hemlocks are having a far-reaching effect on the ecosystem. Most of these effects are thought to be negative, however, the hemlock varnish shelf mushrooms are relishing in the deaths and experiencing a population explosion.
The hemlock varnish shelf mushroom resembles a well-known Chinese medicinal mushroom, the reishi mushroom. In fact, the reishi and the hemlock varnish shelf share the same genus, Ganoderma. Gano is greek for shining or sheen, and derma, of course, means skin.
The next time you go for a hike in the woods, keep an eye out for these fungi, and know that you are witnessing an ecosystem changing before your eyes.