Help - Black fungus (I think) on white oak tree

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phil2006

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Hello, I noticed some of the bark on the bottom of a very large oak tree turning black. It feels spongy to the touch (see photo)

Is this a tree fungus? If so, any suggestions on how to treat it and prevent from recurring?

Also - I recently purchased this product for another plant, would this work for the tree also?

Bayer Advanced 701250 Disease Control for Roses, Flowers and Shrubs Garden Fungicide, 32-Ounce, Concentrate https://www.amazon.com/dp/B000NCUW6M/ref=cm_sw_r_cp_api_glt_fabc_AJ5W6BBPR7E9GCGQBGVW
 

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Pull back enough rock that we can see where the trunk flares out to the roots. this is called the root collar and should be at ground level.

Is there fabric or plastic under the stones? If so, get rid of that. It inhibits adequate air and water exchange in the soil.

Nothing you can spray will make up for bad rooting environment.

poke at the bark a little where the black fungal fruiting bodies are...is it loose or tight?
 
Pull back enough rock that we can see where the trunk flares out to the roots. this is called the root collar and should be at ground level.

Is there fabric or plastic under the stones? If so, get rid of that. It inhibits adequate air and water exchange in the soil.

Nothing you can spray will make up for bad rooting environment.

poke at the bark a little where the black fungal fruiting bodies are...is it loose or tight?
Thanks for your reply

unfortunately the root collar is not at ground level, there is soil on top of it. I know this isn’t ideal but I’m limited in what changes I can make to the landscape. There is also a concrete patio nearby that further limits moisture and air exchange.

the bark near the fungus is pretty hard / tight. It’s not quite as hard as the bark further up the tree, but close.

considering the limitations I’m working with, is there anything you can recommend? I’d like to preserve this tree and keep it healthy as much as possible, within the limits of the landscaping that I can’t change. Thanks for your help!
 
Thank you, this is something that I will try to install soon.

In the meantime, is there an immediate treatment available to prevent the spread of the fungus? Maybe a spray or treatment similar to what I mentioned in the original posting? That one seems to be primarily for shrubs and I’m not sure if it’ll be effective for a large oak tree.
 
The fungal fruiting bodies appear to be decay fungus that are living in dead tree tissue. Spraying them with fungicide would be ill-advised and ineffective.
Root and stump rot compromising the integrity of the tree can be a serious safety hazard. I would highly recommend you consider contacting a qualified arborist to access your tree.
 
Thank you, this is something that I will try to install soon.

In the meantime, is there an immediate treatment available to prevent the spread of the fungus? Maybe a spray or treatment similar to what I mentioned in the original posting? That one seems to be primarily for shrubs and I’m not sure if it’ll be effective for a large oak tree.
Nothing you can spray will make up for bad rooting environment.
 

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