Oct 08 2011

Glow in the Dark

Published by at 8:47 am under Plants


October is a good time of year to see wood glow in the dark. 

The phenomenon is called foxfire and is most often caused by the honey mushroom (Armillaria mellea), native to eastern North America.

Armillaria mellea feeds primarily on hardwood and is most often noticed when it produces fruit — the mushrooms.  Mushrooms are similar in function to apples.  There’s a big plant structure that produces apples, but in the case of honey mushrooms you can’t see the “plant” until it glows.

The glowing comes from its rhizomorphs that look like long, black bootlaces and grow under the bark of dead trees, downed logs, old roots and stumps.  They also grow on living trees which they eventually kill. 

The faster they grow, the more they glow because their feeding process produces light.  Their bioluminescence is a chemical reaction that’s the opposite of photosynthesis.  The tree they’re consuming used CO2 + light to produce organic (carbon-based) material + oxygen.  The fungi use luciferin molecules to combine organic material + oxygen to produce CO2 + light.  Pretty ingenious, eh?

Finding foxfire is problematic, especially for city folks like me.  The light produced is a faint green or blue glow that’s easily swamped by man-made light.

The habitat and weather must cooperate too.  The infected wood has to be damp — not too wet, never dry — and the best temperature is 77oF though anything above freezing is acceptable.  Summer heat (86oF+) shuts down bioluminescence which makes autumn, with its early sunsets and cooler temperatures, an optimal time to see it.

I’ve never seen foxfire but that’s no surprise.  I’d have to drive to a very dark place (how far?) and wander in the woods at night looking for a faint glow, hoping I don’t encounter a mammal I don’t want to meet.  Spooky!

Have you seen foxfire?  Where?

(photo of foxfire in Allegany State Park, New York by highlatitude on Flikr, Creative Commons license.  Click on the photo to see the original)

19 responses so far

19 Responses to “Glow in the Dark”

  1. Doug Baumanon 08 Oct 2011 at 9:07 am

    I’ve never seen it, and I’ve lived in the woods all my life. Many times I’ve been out at night (no city lights) and haven’t seen it. Can’t wait to hear where a good place to see this around here is.

  2. Mom Teeon 08 Oct 2011 at 9:23 am

    I always wondered how they got the name of the “Foxfire” books of the 60′s/70′s (right date?). Now, I know.

  3. John Englishon 08 Oct 2011 at 11:16 am

    I’ve seen Jack-o-lantern mushrooms at Todd Sanctuary, but never foxfire. The mushrooms are a rather startling sight when you come upon them unexpectedly!

  4. Joshon 08 Oct 2011 at 8:46 pm

    Do you happen to know why on earth a fungus would want to waste carbohydrates (or other organic molecules) on emitting light? Typically its more efficient to convert them into more useful forms of energy, such as chemical energy in the form of ATP that can be used to perform the necessary reactions for life. I can’t imagine what evolutionary advantage it would give the mushroom to glow in the dark (probably due to my lack of imagination).

  5. Kate St. Johnon 09 Oct 2011 at 6:57 am

    Seems it’s not a waste to the fungus because gets its energy using this chemical reaction: the more it grows the more it glows. It’s ingenious that one chemical reaction (bioluminescence) is the opposite of another (photosynthesis). Nothing is lost.

  6. Joshon 10 Oct 2011 at 4:48 pm

    Perhaps I’m just misunderstanding, but I can’t see how using useful energy like carbs to make useless energy like light is anything but wasteful. Also, I don’t see why an organism would evolve something like bio-luminescence if it didn’t give it an evolutionary advantage. Just saying. . .

  7. jeanon 25 Oct 2011 at 8:26 am

    i have seen foxfire in eastern tn.

  8. David Son 24 May 2012 at 2:15 pm

    Sorry to “reactivate” an older conversation; I have been ~8 months away from Kate’s blog, but would like to weigh in on this one.

    I think that when the organic matter (i.e. mostly cellulose or complex sugars) is broken down by the fungus, a photon is naturally emitted as a part of the process. It is useless to the fungus, but it is not deliberate “waste”. The energies made available from a chemical reaction are a function of the bonds that are broken. Some higher energies cannot be captured, and are lost as a photon (or as a low level of heat).

    It is mistaken to think that every extant biological trait exists because it confers an advantage. Some characteristics persist simply because: (1) they were created ‘randomly’, as all traits are, AND (2) the trait confers no DISadvantage.

    The light emission occurs because chemical reactions are occurring. The fungus is using what chemical energy it is able to use easily and/or efficiently. The light probably confers no advantage. The light also probably confers no disadvantage.

    Amillaria mellea is a wonderful edible mushroom (to be eaten with extreme caution!!). If the woods were full of people (or light-sensitive animals) looking for them, only the least light-emitting specimens would survive. Either the light emitting trait would diminish/disappear, or the mushroom might.

  9. Teri Son 04 Oct 2012 at 3:45 pm

    Hi All. I found this discussion while researching the science specifics of “Foxfire” for my friends and thought I would share my experience with Foxfire. We spotted some last night while horseback riding at Lord Stirling Stables in Somerset County N.J. It was dark and very foggy – about 98% humidity and 71 degrees F. We were on wooded riding trails near the Great Swamp Refuge. This is not the first time I have seen Foxfire on these paths. Back in July it was even more obvious. The type here looks like glowing embers under the leaves or fallen tree trunks. I even had it “displaying” along my driveway at home (NJ) in July which was a surprise. I hadn’t picked up old leaves and dead tree bark under my forsythia bushes, giving it an ideal environment , I suppose. It was very humid and warm. It cannot usually be seen there. The conditions have to be just right.

  10. Dougon 06 Oct 2012 at 12:53 am

    I have seen foxfire in Western Washington state. I was 8 years old and we were leaving my cub scout camp. I looked up the trail and saw an entire stump glowing in the dark. At first I thought I was seeing things, but as we got closer I realized that it was a glowing stump. I broke off a piece of the stump and took it home. It stopped glowing once the wood dried out.

  11. Faithon 14 Oct 2012 at 10:42 pm

    I live in Missouri and we saw some last night. We had the coon dogs out and while stopping to listen to them bark to see where they were, we noticed a glowing on a log by us. I picked some to get a better look at it at home under the light.
    It looks like a small mushroom you might see anywhere in the woods. The next day there wasn’t any glow left. I heard older folks talk about it and
    they said it was rare to see it. The temperature was about 70 degrees that night.
    I have seen it once before about 6 or 7 years before around the same area. Conditions must be just right for it to grow here.

  12. Devonon 29 Nov 2012 at 6:25 pm

    Thank you for this description and introducing me to the term “foxfire”. I saw this phenomenon about 15 years ago and had no idea what it was. As far as we could tell it was just a piece of bark that could glow in the dark. When looking at the bark under the light, we could see nothing remarkable about it. There was no visible trace to where the glowing material was.

    I always guessed that it was some sort of fungus but could never figure out what kind. I even asked people who I believed to be experts and they had no clue. I’ve often gone back to the same area to try to find more but never saw it except for that one year. I think I might have to go back and check again. But yes it doesn’t glow very bright so if you’re hiking at night with a flashlight, you probably won’t see it. It was one of our favourite past times at the time to do “night hikes”; hiking on trails far away from the city lights without the aid of flashlights. This is probably why we were able to find it.

  13. dana Foxon 04 Aug 2013 at 9:09 pm

    woke up last night at our campsite on the little emory river in tennessee and was amazed to see an entire two ricks of stacked hardwood fire wood glowing with bio luminescence. It was eerie, beautiful and sorta made me feel bad to add more of the wood to the fire. What a beautiful site though!

  14. Roger Slightomon 27 Jul 2014 at 10:33 pm

    We were camping last night and woke up before sunrise to find wood chips glowing. We had created the chips the previous night in the process of cutting firewood. Neither of us had seen it before. The conditions must have been just right, cool & humid but not raining. It looked magical because it was sprinkled all over the ground.

  15. Roger Slightomon 27 Jul 2014 at 10:41 pm

    I forgot to mention that we were camping by a lake in central Illinois.

  16. Cindy Greenowon 28 Jul 2014 at 6:56 pm

    Just seen this phenomenon 2 days ago, very weird camping in a field in Devon owned by friends who cut up a fallen tree for the fire. All the wood glowed including the chips on the ground! Never seen anything like it, totally amazing experience.

  17. Amanda Mon 31 Aug 2014 at 4:16 pm

    Last night at our camp site in Ohiopyle State Park (Pennsylvania) my husband and I witnessed this for the first time ever. I must say it was pretty amazing!

  18. thomas zuron 05 Sep 2014 at 2:41 am

    Just experienced this for the first time tonight sept.5 2015. I have worked for the forest service in many ways and spent many nights in the mountains without ever setting anything like this. Im in western mass breaking trees up for a fire and get very spooked by this phenomenon. Excitedbut

  19. Belinda Ton 22 Sep 2014 at 1:33 am

    It’s Sept. 21st 2014. My husband and I are camping in Willamette National Park at a place called McKenzie Bridge campground. We split some wood earlier in the day from a short log left behind from a previously cut downed tree. As we collecting our fire wood up for our next stay and because we thought it was getting ready to rain. My Husband started picking up the cut pieces,we noticed something glowing on some of them. First reaction was to check it out in the bright light. We seen nothing but a nice piece of hard wood so we placed in our black trash bag to our surprise you could see it glowing even brighter through the black trash bag. Once again Nature has another beautiful surprise to show off. The last time we seen something similar was in the Ocean while sailing in the night. I felt so fortunate to be able to witness it first hand with my hubby. Definitely a night to remember. Thanks so much for the explanation. So very cool:)
    B & B Tackett

Comments RSS

Leave a Reply

Bird Stories from OnQ