Indirectly yes, it is killing the maple. Bracket fungi like this are indicative of an interior wood rot, usually heartwood rot. They are just the visible signs of a fungal pathogen that has already infected the tree.

Even though the tree may appear healthy, by the time the bracket mushrooms appear the rot is already well advanced. There is no cure. The tree may appear outwardly sound for some time but its structural integrity has been compromised by the rot and it could split, come apart or come down at any time.

You should consider removal before that happens.

thank you. i will remove it and spray with spectracide. maybe the tree will survive. i definitely knew that i might kill it 4 or 5 years ago by cutting back other trunks

You meant removal if the tree. yes i will coonsider

Yes, I meant removing the tree :-) Removing the mushrooms now will have no effect, one way or the other. Neither will spraying with any fungicide at this stage.

You are developing a hollow tree trunk. It can snap under duress. Comparing the leaves in the picture to the tree trunk I have to wonder what kind and how big is this maple? Show us the rest of the tree before rushing to chop it down. Hollow trees can linger for a long time.

The black spray paint on the cut marks in the trunk is not helping anything.

This is the tree

It is a sugar maple. tough trees, the black paint is a spectracide i have been using past 7 years on areas i cut. alas, looks like too much for the tree to recover from

That is the kind of maple you may not want to fall on its own depending on how much land you have for it to fall on.

If it's out in the woods like that, I certainly never bothered cutting down any tree where I once lived in a wooded area, unless they were close to the house or car.

i will remove it and spray with spectracide. maybe the tree will survive.

==>>>

tree time is counted in decades ...

this tree will not survive interior rot.. period.. though it might take a decade for it to fall over in a storm.. as noted.. it doesnt appear it will fall on anything so leave it be ....

and a quick google of spectracide indicates its an insecticide .. which i have no idea what it would do for rotting inter structural wood.. so dont use it.. it wont do anything... in theory.. that is one definition of polluting ...

in essence.. the bones of your tree are dissolving.. and if you lost all your bones.. sooner or later you would fall down .. the interior wood of a tree is its structure.. or its bones.. with no structure.. you have no tree ..

and when it does fall down.. odds are.. it will resprout.. because it will have a huge root mass.. and a great potential to live... so.. ig you dont want that.. you would have to cut it down.. and apply a stump killer..

lets see if i can find pics of what s happening inside your tree..

ken

https://duckduckgo.com/?q=interior+of+tree+rotting&t=ffab&iax=images&ia=images

Thank you all.