Question
Oak tree fungus
JIm- We chatted last week. Here is a picture of the fungus. You may recall the tree incurred a split in the main "V" which extended 30" down the trunk. It opened to approx 1/8". I sprayed the crack with insulting foam to rid ants. The fungus started growing just after I applied the insulating foam.
The tree appears very healthy other than this fungus.
AnswerThese are the fruiting bodies of a decay fungi. I am not real sure which one but it really does not matter to the treatment. If I had to guess I would say it was one of the White rot fungi. A decay fungi enters the woody part of a tree through breaks in the bark. Over time the fungi eats away at the woody in side the tree trunk and in many years will cause the trunk to become hollow. A hollow tree is not really that bad. the tree can lose some strength but the health of the tree is not effected. I would think the bark wher the fungi conks are growing is dead and will become loose and slough off as time goes by. There is not a fungicide that will control the decay fungi or the fruiting conks. Removal of the spore-bearing structures (called conks or brackets) from the bark surface does nothing to control wood decay -- the threadlike hyphae of decay fungi are present in the wood beyond the immediate area of the conk. Wound treatment paints do not prevent invasion of the wound by wood decay fungi and therefore are of little benefit. Maintaining tree vigor through proper pruning, irrigation and fertilizing practices will help to reduce potential decay problems by promoting the trees natural wound response processes.
I would fertilize the tree with 10-10-10 fertilizer at the rate of 1 lb per inch of trunk diameter scattered around the tree and watered in good. Do this in the spring. If you put the fertilizer out just before a rain storm you will not have to water it in.
Signs that the tree is getting into trouble with strength is large limbs breaking and the end of the limb near the trunk is hollow. This would mean the decay has grown into the upper parts of the tree and the falling limbs could be a hazard if buildings or structures were near the tree.
In your case this should be many year down the road and maybe not at all.
If the bark where the fungi conks are growing gets loose you can cut it off back to solid bark and this will help the wound heal faster but an area this large will take many years to heal over.
