I have an oak that presents many ants on its bark, and I feel that its bark looks sick (even though I'm not an expert, so it's just a feeling). Furthermore, there is a big fungus at the trunk's base. Here are some images:

Photo of the whole oak

Here are three photos of the bark:

Photo 2

Photo 3

And here's a photo of the fungus:

Photo of the fungus

Is this oak sick? If so, what can I do in order to treat it?


Here are other photos of the fungus:

Photo 2 of the fungus

Photo 3 of the fungus

Photo 4 of the fungus

Photo 5 of the fungus

  • Can you take pictures at other angles so we can see what fungi it is? Jul 24, 2018 at 4:34
  • Sure, I'll upload other photos of the fungus as soon as possible.
    – mark247m
    Jul 24, 2018 at 13:49
  • What about the underside? so we can identify the specific type of mushroom you have, and tell you if it's edible or not? Jul 24, 2018 at 16:16
  • The fungus is very close to ground, so I had an hard time on taking a photo of the underside. The best result I was able to get about the underside is in the third last photo.
    – mark247m
    Jul 24, 2018 at 21:49

2 Answers 2


I'd strongly advise you to call an arborist to inspect the tree - that fungal growth might be evidence of foot and butt rot, and if it is, the tree may either be unsafe already, or will become so in fairly short order. Given the tree's proximity to a building, I wouldn't wait any time at all before getting it checked out. If it is foot and butt rot, by the time a fruiting body appears, it's usually already too late, but sometimes trees can remain stable with this infection for a year or three.


Finally, I've found images of Ganoderma that are similar to the growth on your tree. I think this fungus is Ganoderma lucidum, which is associated with foot and butt rot, scroll down to the picture on the left showing an oak with this fungus http://www.missouribotanicalgarden.org/gardens-gardening/your-garden/help-for-the-home-gardener/advice-tips-resources/pests-and-problems/diseases/rot/ganoderma-root.aspx

  • some fungi that help trees also grow at the base of them. Jul 24, 2018 at 4:33
  • 1
    @blackthumb if you are talking about symbiosis where mycelium and roots intertwine in the ground, yes. Growth like this, no.
    – Stephie
    Jul 24, 2018 at 9:12
  • i'm talking about fruiting symbiotic mushrooms Jul 24, 2018 at 11:58

If it is, as it seems to me, a Fistulina Hepatica, this fungus does not mean your tree is sick.

The species is fairly common, and can often be found on oaks and sweet chestnut, from August to the end of autumn, on either living or dead wood. It has a tendency to impart a reddish-brown stain to the living wood of oaks, creating a desirable timber type From Wikipedia

The rot caused by Fistulina on oaks does not affect the strength of the wood, so it is appreciable as cabinetwork for wood workers because of the nice wood coloring it gaves.

About the wound in the middle of the trunk, it looks completely healed, so probably no harm here either.

Anyway, if you can take some professional advice this is always better.

  • 1
    The fungus you mention, growing on an oak, often causes brown rot, as mentioned in the link you provided. That will kill the tree...
    – Bamboo
    Jul 24, 2018 at 11:24

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