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Mystery Photo


If you think you might know what this black, crusty substance is, please go to my blog, scroll down to “Comments” and enter your guess as to what it is and how it got there. Answer revealed tomorrow. (Hint:  It is not a gall, and it was found on a Speckled Alder branch.)

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33 responses

  1. Betsy Hawes

    An egg mass…Of an insect?

    October 19, 2016 at 7:31 am

  2. Dara Johnson

    Fungus on a cherry tree

    October 19, 2016 at 7:36 am

  3. Alice Pratt

    Black knot disease, caused by a fungus.

    October 19, 2016 at 7:58 am

  4. Laura Alexander

    pin cherry black knot

    October 19, 2016 at 8:00 am

  5. Barbara Hager

    It looks like frass, possibly aphids?

    October 19, 2016 at 8:04 am

  6. Vikke Jas

    Smut… although smut likes the grass family. Could it have been passed along from an herbivore that had contact with a grass, then investigated whether the alder was yummy as well?

    October 19, 2016 at 8:09 am

  7. Rod

    Chaga fungi (Inonotus obliquus).

    October 19, 2016 at 8:09 am

  8. Rod

    Chaga fungus (Inonotus obliquus)

    October 19, 2016 at 8:11 am

  9. Pam Katz

    Can you please clarify a group question: Do the seeds pop on witch hazel after the flowering occurs, the same fall, or the following year?

    “I was so much older then, I’m younger than that now.” Bob Dylan

    Sent from my iPad


    October 19, 2016 at 8:16 am

  10. Kathly

    I don’t know the name but it is a growth on birch trees that is collected and used in teas, etc. for health and medicinal purposes

    October 19, 2016 at 8:19 am

  11. Bill On The Hill...

    I have seen this since I was knee high to a grass hopper while exploring the woods, never really had a clue as to what it was, perhaps a fungus of some kind?

    October 19, 2016 at 8:33 am

  12. Kathy Schillemat

    Have seen this before, but can’t remember the cause. Aphids?

    October 19, 2016 at 8:35 am

  13. Kathy Schillemat

    It’s not Chaga. I’m pretty certain of that.

    October 19, 2016 at 8:38 am

  14. Elaine Schmottlach

    Black Knot?

    October 19, 2016 at 8:47 am

  15. Tami

    Looks like black knot or a similar fungus.

    October 19, 2016 at 8:51 am

  16. Frances

    Possibly black knot?

    October 19, 2016 at 9:26 am

  17. jmontagueaudubonorg

    A chaga mushroom! They grow mostly on birch around here, but since alder is in the same family, you can sometimes find it on alder too.

    October 19, 2016 at 9:35 am

  18. Bradley Wheeler

    That looks like the fungus that feeds off aphids’ honeydew.

    October 19, 2016 at 9:39 am

  19. black knot

    October 19, 2016 at 9:41 am

  20. Alan M Stoops

    Since you state that it was found on speckled alder, and it’s not a gall, I wonder if it’s something left by the woolly alder aphid (I think that’s what it’s called, and I’m resisting Googling for answers until after I’ve posted my guess). Perhaps the aphid “wool” gets crusty when it ages? After the aphids die? The “wool” is frass or some other type of exudate from the creature.

    October 19, 2016 at 9:55 am

  21. Susan E. Costanza

    This is the remainders of hatched moth eggs, on a tree branch.

    October 19, 2016 at 10:25 am

  22. Penny Jessop

    My guess is Clinker Polypore, Polyporaceae Aphyllophorales.

    October 19, 2016 at 10:27 am

  23. Some kind of fungus? Looks sort of powdery/sooty, like mold growing over a dried egg case.

    October 19, 2016 at 10:36 am

  24. Annie

    Wooly aphid?

    October 19, 2016 at 11:18 am

  25. It looks like that black, tarry fungus that appears on fruit trees, only sort of dried out.

    October 19, 2016 at 11:32 am

  26. Crown Gall

    October 19, 2016 at 11:58 am

  27. Svetlana Tsalik

    Does it have something to do with ants farming aphids?


    October 19, 2016 at 12:13 pm

  28. Kathryn

    What is your address so I can send a check?

    October 19, 2016 at 4:21 pm

    • 134 Densmore Hill Road, Windsor, VT 05089 – thanks!

      October 19, 2016 at 8:50 pm

  29. Is it something to do with ants farming aphids?

    October 19, 2016 at 5:19 pm

  30. Bobbie Rausch

    I think this is Apiosporina morbosa, or black knot, a parasitic fungus.

    October 19, 2016 at 7:32 pm

  31. ann


    October 19, 2016 at 8:11 pm

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