Climacodon septentrionalis, or the Northern Tooth Fungus, is considered inedible because of its bitter taste and rubbery texture. It is a parasite of living hardwood trees, showing a preference for maple, beech, and ash.
There is no cure for an infected tree. In fact, by the time you see the elegant fungal leaves, significant damage has already occurred.
Climacodon spores are carried by the wind and enter trees through open wounds. As the fungus grows, it secretes enzymes into the heartwood, the core of the tree through which water and nutrients are transported. The enzymes break down the heartwood, releasing a soup of nutrients which Climacodon then absorbs. As the heartwood is destroyed, it becomes white and spongy.
Climacodon is a short-lived species, surviving less than a year, but the hollowed section it creates becomes a permanent weak spot. The tree may live many years—even decades—but eventually snaps, often during a wind storm.
The mushrooms we see are the fruiting bodies, or reproductive extensions of the fungus. The closely packed, spongy hairs below the fungal leaves contain spores. The spores are released to the wind, and the cycle renews.
Kuo, Michael, Climacodon eptentrionalis. MushroomExpert.com.
Roberts, Mariana, Northern Tooth Mushroom – Climacodon Septentrionalis. YouTube.
Nagy, Tom, Foraging Fun: Climacodon Septentrionalis. Outside the Hops.
Volk, Tom. Tom Volk’s Fungus of the Month for February 2001. Tom Volk’s Fungi. Department of Biology, University of Wisconsin—La Crosse.
The Northern Tooth Fungus, Forest Floor Narrative.
Fungus Nutrition. Britannica.