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Northern Tooth Fungus

9-22 northern tooth fungus 159Northern Tooth Fungus, Climacodon septentrionale, is an unusual combination of both a shelf (also called bracket) fungus as well as a toothed fungus. Typically a shelf fungus produces spores inside pores located on its underside. Northern Tooth Fungus, however, produces spores on pendant, spine- or tooth-like projections on its underside (see insert). This fungus usually has several tiers of “shelves” that grow in tight, thick layers, and change from white to light tan as they age.

Northern Tooth Fungus is a parasite of living trees, especially Sugar Maples, and it causes the central heartwood of the living tree to rot. The only sign that a maple has this fungal parasite is the appearance of these shelf-like fruiting bodies in late summer or fall. Often trees with this fungus become weak and are blown over by the wind. As with most shelf fungi, it is considered to be inedible. (Thanks to Jeannie Killam for photo op.)

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9 responses

  1. Clay Smith

    Great photo and description! While most shelf mushrooms are inedible, the relatively common Sulfur Shelf can be delicious.

    September 23, 2015 at 9:43 am

    • Thanks, Clay. I edited my post to read “most” shelf fungi as I recalled Chicken of the Woods as being a delicacy!

      September 23, 2015 at 9:54 am

  2. Kathy

    Hericium or lion’s mane is another fungus that grows on trees (mostly beech) and while it isn’t a shelf mushroom in form, it is also very edible and delicious. Another edible mushroom that grows on trees is the oyster mushroom, which I think could be considered a shelf mushroom. I have harvested a huge oyster mushroom in the past.

    September 23, 2015 at 10:56 am

  3. Cheron barton

    Yummmm!! Lol

    Sent from my iPhone


    September 23, 2015 at 8:10 pm

  4. Cindy

    As a wild mushroom lover, this post felt a tiny bit negative – like the mushrooms are insidiously killing the poor trees. Mushrooms already get so much “bad press”. My feeling is, if it’s out there happening in nature, it’s probably an important part of nature’s plan. Times when it doesn’t “work” for humans, we vilify it (not that you went that far, Mary. Love you and love your column!) But many mushrooms are symbiotic and help trees. Others are critical in the “breaking down” part of the life cycle process. Mushrooms rock! And not just the delicious ones!

    September 24, 2015 at 6:01 am

    • I couldn’t agree more, Cindy. Last thing I intended or thought I was doing was villifying mushrooms! I just found it fascinating that they could have that large an impact on a tree. No judgement intended! Thanks for putting in a good word for fungi!

      September 24, 2015 at 7:46 am

      • Cindy

        Yes. Your championing of (ALL parts of) nature is obvious to anyone familiar with your work. No offense intended on my part either. Happy Trails!

        September 24, 2015 at 8:26 am

  5. Jack Nelson

    The Northern Tooth, when fresh, is considered to be edible, according to the Audubon Field Guide. I haven’t tried them myself, but they are plentiful now. Thanks for all the great observations.

    September 24, 2015 at 2:18 pm

    • It’s not poisonous, but I believe it’s quite bitter (even when young) and very tough as it ages…

      September 24, 2015 at 5:28 pm

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