Question
I have a red oak tree approximate. 100' tall.  The base is larger than the trunk (mushroomed) I have been told the tree is under stress and may have center rot.  The tree appears to be healthy with many large strong branches. What is your thought, is the tree rotting?  Should it be removed?

Answer
No If the foliage is green and full the tree is healthy. It sounds like the wood in the center of the tree is decaying and the tree may have some hollow places in the trunk. The living part of a tree is just under the bark and the bark protects the cells from decay fungi. When there is a wound to the bark decay fungi can get into the woody cells and start the eat away at the cells. carpenter ants some times make their nests in these decaying areas. The woody cells are dead cells and not associated with the healthy of the tree except for strength.

Trees can and do live many many years with their trunks completely hollow. Trees have the capability to seal off the decay fungi and slow the growth of the decay. IF the large limbs start to break off and the end near the trunk is decayed or hollow then the tree may have reached a point that it could be a hazard. And then it is only a hazard if it is locates near a structure that could be hit by a falling limb. Yours sounds a long way from that stage.

I would fertilize the tree with 10-10-10 fertilizer at the rate of 1 lb per inch of trunk diameter and water it in  good, or wait just before a rain storm and fertilize and you will not have to water. This will increase the health of the tree and help slow the decay fungi. I would do this now and again after the leaves fall in the Fall.


The heartwood consists of the growth rings in the center of the trunk. They are aged sapwood and thus form part of the Xylem. They tend to have a darker color than the sapwood, because they no longer transport any water and are therefore much drier, and they tend to be clogged up with gums, resins and other substances, depending on tree species. Because they are no longer taking part in the trees vital processes, they can be said to be 'dead wood'.

A hollow tree is a tree where the heartwood, which has less resistance to rot than the living parts, has gradually decayed away. Surprisingly, this makes no difference to the vigor of the tree and may even enhance it ability to stand up to severe gales, due to the immense strength of a tubular structure. So it is important to realize that a tree with decaying heartwood is NOT a decaying tree! It is a natural process in many older trees