Asked on May 30, 2013

Help me identify this green stuff on my trees

Jeff C
by Jeff C
This green mold/algae looking stuff is all over my Japanese maple. I've discovered it on the bark of some other trees as well. Does anyone know who I would take a piece of tree bark to in order to identify what it is?
  37 answers
  • Lyn Lyn on May 30, 2013
    It's tree moss. It is very common and does not hurt the tree. It usually grows on the side of the tree that gets less sun which means it is more moist. For more information, google tree moss.
  • Gwen Gwen on May 30, 2013
    county ag dept?
  • 360 Sod (Donna Dixson) 360 Sod (Donna Dixson) on May 30, 2013
    You have lichens. They will not harm your tree. Check them out, they are very cool organisms!
  • Rosemary N Rosemary N on May 31, 2013
    I'm in the lichen camp, too. Don't worry, it won't hurt your tree.
  • Rev. Brian Moffit Rev. Brian Moffit on May 31, 2013
    It helps you find north. ( least amount of sun) Old Indian knowledge.
  • Sabina Sabina on May 31, 2013
  • KMS Woodworks KMS Woodworks on May 31, 2013
    Lichen....which comes in three basic growth forms. What you have here is the Foliose type.
  • Kerrie Marquart Kerrie Marquart on May 31, 2013
    Lichen and it is harmless as it only uses the tree as a host just as Spanish Moss does and does not take any nutrients from the tree but the moisture in the air. It usually is more prolific on dead branches and bark.
  • Jeff C Jeff C on May 31, 2013
    The reason why I posted this is because I figured this stuff all over the tree was one of the reasons for my maples demise. Looks like Lichens are harmless although they sure do cover a lot of tree bark. Thanks all for the help.
  • Terry G Terry G on May 31, 2013
    I had something that looked like this on an azalea- which was dying where this was. So perhaps there is bad lichen?
  • Cyndi Neumann Cyndi Neumann on Jun 01, 2013
    Lichen and Algae grow on many of the trees here in North Carolina! They vary in types and colors, I think they add a bit of interest! Smiles, Cyndi
    • Cindi Cindi on Dec 21, 2020

      I purchased firewood that had this on it. Is it safe to use/burn in my fireplace?

  • Eulalia Eulalia on Jun 01, 2013
    Lichens, if I remember correctly, are actually edible! Something to keep in mind in case of a food shortage!!! LOL.
  • Gina Gina on Jun 01, 2013
    Very good to know. I have this on a couple of my trees as well. Thanks for all of the info.
  • Home Repair Tutor Home Repair Tutor on Jun 01, 2013
    Thanks so much everyone for your comments, we have the same thing on our trees and I was worried. But you've calmed my fears :)
  • S S on Jun 01, 2013
    Lichens won't harm it, but it does indicate that the tree may be stressed. I googled the subject, because I was only partially recalling my microbiology. I found an article explaining the relationship between lichens and trees: have a mutual relationship; they prefer trees under stress, but don't harm them. If the trees are valuable it might be good to call a tree expert and see what your maples need to grow properly or ask a nursery what you should be feeding them. We need to feed our trees regularly.
    • Barbara Ristaino Barbara Ristaino on Aug 23, 2017

      I had heard that they grew on stressed trees as well. I think this is important for us to know. Thanks for the info.

  • Gretta G Gretta G on Jun 01, 2013
    Not algae, lichens. Enjoy the rustic look-it wont hurt anything!
  • Ronda Henderson Ronda Henderson on Jun 01, 2013
    Once dried, it can be used as a burns very hot to get the coals going. It is also called "old man's beard" and is not hard on trees.
  • Riggs Laughlin Riggs Laughlin on Jun 01, 2013
    Ronda i`m very good in home repairs......whats wrong with the coal mixed up stuff
  • KMS Woodworks KMS Woodworks on Jun 02, 2013
    @Sue The lichens do not "target" sick plants. They are simply growing where more favorable conditions exist. An example might mean a drought stressed plant produces less foliage, so there is more "light" available for the lichen to grow. They still follow the basic equation of air, sunlight and water combined with a physical substrate on which to attach. Colonization is slow as these plants are fairly slow to grow and spread. One of my botany professors ( I have a masters in biology with a minor in Botany) recalled a study that was done on tombstones and lichen. This type of lichen was the crusty kind found on rocks. A relationship was developed based on the "diameter" of the colony and the age of the tombstone. As a pioneer specie, they often start and small speck and grow out in a radial configuration. Where potential issues can arise is that the lichens will contain organic material. They also "trap" moisture. As the plant lives and dies the organic material left behind and trapped moisture can lead to other secondary issue. Molds and fungi feed on organic material and if this is trapped in nooks and crannies it can be harmful to the plant or other decking, roofing etc. check out this article I wrote on mossy roofs. the problem here and in some lichen cases lies with accumulations of organic matter and moisture.
  • S S on Jun 02, 2013
    I didn't use the word target, but if they are stressed they are more likely to have lichen, but they are not bad for the tree. However, the tree may have some other stressor going on that one might want to check out. Now I didn't throw my degrees at you.
  • Darlene T Darlene T on Jun 18, 2013
    I've heard that were there is Lichen, the air is supposed to be more pure (not much air pollution) I live in the mountains of West Virginia and the Lichen is all over my trees... all of them!
  • KMS Woodworks KMS Woodworks on Jun 19, 2013
    @Darlene T I have heard this as well. The term for this is "indicator species" The reason this works with lichen is they are very sensitive to issues with the rainwater. As they do not get their water from the ground like most other plants. The minerals in the soil help "buffer" the acidic conditions of rainwater that is tainted by sulfur dioxide (acid rain producers). Some years back I got to attend the founding meeting of the US's Acid Rain Coalition. I also learned lot about this when getting my masters in Bio. (Botany Minor)
  • Darlene T Darlene T on Jun 19, 2013
    KMS... question, what do you know about ALKALINE water, seem that is what our well water is. We don't water out plants with it, especially tomatoes, turns the lower leaves yellow. We just collect the rain water runoff from our roof and during hot days we water with that.
  • KMS Woodworks KMS Woodworks on Jun 20, 2013
    @Darlene T Some alkalinity issues can be corrected with a "water softener" as these minerals contribute to the problem. RO (reverse osmosis) is another method, Mineral acid addition is yet another. The best way to go about this is to have your water tested by a lab, this will let you know exactly what you have and the concentrations of the "mineral" or ion components. Some folks will even test their water a various times of the year as there is often seasonal variations. ( this is more dependent on the depth of your well) Once you have a water "profile" identified, you can target a treatment plan to correct it.
  • Darlene T Darlene T on Jun 20, 2013
    Thanks for the info KMS
  • Bobbi Harrigan Bobbi Harrigan on Jul 27, 2013
    I have tis on my trees too..I didnt have it TIL AFTER HURRICANE KATRINA..I live in the South part of La.. the outerskirts of New Orleans..glad to know it wont kill anything
  • Linda K Linda K on Jul 27, 2013
    Brian Moffit, I do believe that it is the *moss* that you want to look for on the north side of the trees, not the lichens. Seems to me our lichens are on all sides, especially the south. :-)
  • KMS Woodworks KMS Woodworks on Jul 28, 2013
    @Bobbi Harrigan unlike moss...lichens can tolerate a lot more sun. The hurricane may have opened up your yard that is now letting in more sun...and now you have some lichen.
  • Bobbi Harrigan Bobbi Harrigan on Jul 29, 2013
    thank You so much
  • JohnQpublic JohnQpublic on Mar 30, 2014
    Trees are all dying in my yard. Pine, hardwoods, ranging in height from 10 feet to 40 feet you name it. Only common denominator is this lichen gone viral choking them off which you all purport to be inert and not harmful ? And someone writes it attaches to trees which are stressed ? reason for ALL trees in this area to all of a sudden become sickened with dying branches only shortly after seeing this stuff show up.....( last 3 years )and if it just "shows up" some time after a storm as someone suggests, it was probably just carried there by the winds infecting your yard....
    • Tammy Miller Tammy Miller on Jul 30, 2018

      Your absolutely right, I agree . What is this lichen algae crap all over my bushes n trees??!! It's on my maples, oaks, pine, japonica, rosesharon, pretty much my whole property is dying! Any new news what this sh#t is?

  • Lisa brunson Lisa brunson on Apr 06, 2014
    My yard is surrounded on 3 sides with azaleas and this has taken them over. The branches are dying when it gets on them. The Clemson Extension said to use Bonide copper fungicide on it. Safe for organic gardening. When I prune after they get through blooming, I am going to try it. Wish me luck.
  • Cheryl grant Cheryl grant on Sep 19, 2017

    Does anyone know what this particular type on lichen is called??

  • GEn GEn on Jul 06, 2018

    JohnQpublic, I agree with you. In my bush walk this morning I was checking out all the trees with this lichen, they were all mainly dead and dying trees. So its not a good sign for your living tree to have it. We need to rescue our trees. I've started spraying them all with garlic water, vinegar on the branches. It has stopped the lichen getting worse. My curry leaves were full of black spots. So am trying to recscue my curry leave tree.

  • Landsharkinnc Landsharkinnc on Jul 30, 2018

    lichen --- usually sign of a not healthy tree ...

    • Amy Amy on Mar 29, 2022

      Right so why is it that I’m walking through an entire neighborhood of them when I go to work? I say they’re dying from the emf that is ever increasing in our lives. Then the lichen comes in to do its job.

  • Jack Potter Jack Potter on Apr 24, 2020

    I have determined that the white fungus like growth on my beautiful Japanese maple is lichen. Apparently its not detrimental to the tree, just looks bad.... Good to know. I usually fertilize my garden (where the tree is) with Miracle grow plant food every two weeks during the growing season, but my question is.... should I be using a stronger fertilizer just for the tree. I was worried it may do harm to the tree if it got more than what was needed. In other ways the tree seems very healthy but I am no arborist!! I just want beautiful healthy trees...I was thinking maybe it was getting too much water, but, I dont think thats it. Does anyone know whats best or is the tree not getting what it needs?

  • Cindi Cindi on Dec 21, 2020

    I purchased some firewood that had this all over. Is it safe to burn in my fireplace?

  • Sherry Wyatt Sherry Wyatt on May 21, 2021

    I heard that if you put a few drops of Dawn in a gallon of water and spray it on the tree, it will get rid of that green stuff on the trees.