An online resource based on the award-winning nature guide –

Mystery Photo

12-16-12  mystery photo - yellow birch tree photo (15)Do you know what caused the delicate black etching in this yellow birch?

22 responses

  1. Andrea LaMoreaux

    a fungus of some sort?

    December 17, 2012 at 2:00 pm

  2. No clue, but I think I see a cardinal etched on the right side. It’s gorgeous, whatever caused it.

    December 17, 2012 at 2:02 pm

  3. John DeWitt

    It’s called “spalting” by woodworkers. It’s when bacteria(?) first starts to invade a piece of dead moist wood and begins the decaying process. I would really like to have that piece!

    December 17, 2012 at 2:25 pm

  4. Fungus mycelium…Cabinetmakers and woodturners love the patterns inside wood like this. It’s called “spalting”.

    December 17, 2012 at 2:25 pm

  5. That there is ‘spalting’, caused by a fungus, is it not? I once cut up an old maple tree that had been downed in a storm several years prior. It would have made a woodworker green with envy as it was spalted throughout. The bonus for me was that the fungus was also phosphorescent; I split the wood one sunny summer afternoon, went out to meet some friends for dinner, and came home to a glowing woodpile! Don’t know if was the same fungus, or whether the glowing fungus and the spalted fungus just liked to hang out together…

    December 17, 2012 at 2:27 pm

  6. Michele Miller

    Fungi. Spalting, an early stage of decomposition, is ephemeral. This stage will succumb, relatively soon, to a less beautiful but no less important stage of rot.

    December 17, 2012 at 2:29 pm

  7. Tom Libby

    it’s from fungus, can’t remember the term. I’ve also seen reds, yellows, etc. i would love to have that log for my lathe. It would make a beautiful bowl!

    December 17, 2012 at 2:31 pm

  8. These blogs (and comments!) are soooooo addictive early morning (time diff to Alberta) reading with the morning coffee….!!…….this wood is stunningly beautiful, a magical photograph! Birch is relatively rare here yet there’s an artisan woodworker further south who crafts exquisite bowls just like this. And now I know what’s the deal thanks to reader comments and your ‘mystery’ blog. Thank you!

    December 17, 2012 at 2:45 pm

  9. Birch Borer?7

    December 17, 2012 at 2:53 pm

  10. Laurie allen

    I don’t know, but, it is very pretty

    December 17, 2012 at 3:17 pm

  11. Kay Shumway

    It’s spalting any woodworker knows that. It’s beautiful though. Great picture!

    December 17, 2012 at 3:22 pm

  12. Ruth Donaldson

    Well enough others have told you it fugus and called spalting in the trade – beautiful picture thank you for sharing it.

    December 17, 2012 at 3:34 pm

  13. I don’t know — but it sure looks neat! Could a fungus be responsible?

    December 17, 2012 at 3:46 pm

  14. Oli Z.

    I’ve seen this before, & think it is foxfire, which is a mycelium which is phosphorescent. I find that foxfire tends to grow in golden birch & striped maple, especially at the roots & base, hence my conclusion.

    December 17, 2012 at 4:26 pm

  15. Pat Nelson

    I love spalted pieces, especially birch. I want one of those woodworkers to make me something!

    December 17, 2012 at 4:43 pm

  16. wow, I’d like to have that wood, as would many other woodworkers! It’s called spalting, caused by a fungal white-rot found mostly in hardwoods. It is highly valued by woodworkers for the decorative lines and even streaks of color. If the fungi grows for too long, the strength of the wood is diminished and it eventually totally decays.

    December 17, 2012 at 6:54 pm

  17. Kathy Schillemat

    No, but that is beautiful. I can’t wait to hear the cause.

    December 17, 2012 at 10:47 pm

  18. Willow

    It is brown rot

    December 17, 2012 at 10:58 pm

  19. Trish Adams


    December 17, 2012 at 11:03 pm

  20. Judith Pettingell

    I learned recently that this is caused by fungus growing on dead wood. It can cause gorgeous striations on the wood. When this marked wood is found it is highly prized by wood workers. I only learned this when I found (and bought) a beautiful box with these kinds of markings for my son’s birthday. I don’t know what the wood workers use on the wood to stop the fungus from spreading but I was assured that it was no longer growing.

    December 17, 2012 at 11:20 pm

  21. rick churchill

    There area number of fungi that cause decay within yellow birch and it really doesn’t matter which is the causal factor. More importantly the patterns that develop are present because of the response of the tree to the presence of the fungus or in this case possibly fungi. The tree,even tissue technically non-living, responds to the presence by creating boundaries that may be chemical or physical. These boundaries often can be identified by a change in the color of the tissue at its margin. The ultimate goal of the tree is to compartmentalize-wall off- the organism that is trying to break down tissue. A life lesson- those who are best at strong compartmentalization live the longest!

    December 17, 2012 at 11:25 pm

  22. Donald Patterson

    We woodworkers call it spalting. I only know it to be caused by a fungus

    Sent from my iPhone

    December 18, 2012 at 12:09 pm

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s