Fungus on Yew Tree

I spotted this growing on my Yew tree last week and it has been growing very rapidly. It started out looking like yellow foam.

Does anyone know what it is and if I should try to remove it?

The tree itself is pretty large and is believed to be 200 years+ old and the growth is growing on the trunk itself, but in a section that is full of dead wood.

 

Thanks for the reply!

If it is that would it be wise to try to remove it? Will it be causing harm to the tree if I leave it there?

There are two apple trees near it and I wouldn't want them to be infected with it if it can be avoided especially as they are much smaller.

 

It seems to me that once the fungus start producing the fruiting bodies apart from cutting out the diseased section, (which is probably not possible) there is little you can do.

I bet it goes pretty deep into the tree.

I wouldn't bother too much about it infecting the apple trees, but thats just my guess.

 

Hi YewOwner,

I'd agree with Marley Farley that it is probably Laetiporus sulphureus, but without up-close identification I'm not 100% sure.

The fungus itself, like all fungi, is made from hair-like strands called mycellium (hyphae) that spread throughout the tree and the soil. In order to reproduce, the fungus needs to release spores, and it does so by producing fruiting bodies (conks) on the outside surface of the tree. These spores enter new hosts via exposed wood, usually a recent injury that has damaged the bark. Removal of the conk will not remove the fungus, neither will using a fungicide. Unfortuntely once the fungal fruiting body develops on the surface of the tree the internal damage can be widespread and ultimately fatal.

Laetiporus on a tree can mean extensive internal decay, especially around the butt and lower stem. It causes brown rot, which decays the cellulose and hemi-cellulose of the woody cells, leaving the tree brittle and prone to failure.

My advice would be to get a trained arborist or arboricultural consultant in to take a look. There are all sorts of devices and methods out there of measuring the amount of internal decay a tree has. Once this decay has been mapped it will be possible to draw up an action plan that may yet save your tree from total felling.

With regards to your apple tree; as long as their bark remains intact they should stay quite healthy. Bark acts as a barrier against infection, much like human skin. As long as it's not broken then nothing can get it.


Hope this helps,
Matthew

 

Thanks for your reply.

The apple tree is suffering from wooley aphids. Would that increase the risk to it? Unfortunately the treatment I tried for that didn't seem to be much of a success.

I will see about finding a local expert to take a look. I hope it is possible the tree can be saved as its a lovely old tree and a haven for wild birds, but it is also very close (< 3 metres) to my grade II listed house which means if the risk of failure is increased by too much may cause it to pose an unacceptably high risk.

I have taken a closer look at it and the only area of decay I can see is in this gash with two thicker areas of wood either side of it. I suspect years ago someone took a side branch off at this point and thats how the fungus got in. Right above the gash is one of the four main trunks it has (the tree looks like it is almost four trunks merged together at the base which split off at about 1-1.5m from the ground) so perhaps removal or reduction in height of that trunk might help as the rest of the tree leans away from the house and over a river instead.

 

Quick update on this :

I had an expert around today and he was able to inform me that yes it was Laetiporus sulphureus but in his opinion it wasn't a major problem to the tree. It is growing stronger either side of the damaged wood and is in good health.

He didn't actually map the damage internally, but he did poke the rotten wood and felt it and said even the rotten wood is still pretty solid.

All that needs doing is a bit of work to give it a little more clearance from the house and some other trimming to give my japanese maple some more room.

So overall thats good news.