Hypoxylon canker

[mrtree]

I think the question is what is the black mat stuff. AS you say, impossible to guess at.

 

[JD3000]

Kevin, thats certainly the case as far as I am concerned. Decay mycology is a pretty weak area for me.

 

[KTSmith]

Thanks JD, sorry if I sounded snippy there. We are all here to help each other, at least most of us are if caught on a good day. Part of the dynamic tension here for me is that (1) I'm grateful that the concept has spread that knowing the agent of decay can help in estimates of extent of decay or weakening that is not otherwise visible and (2) I'm also somewhat grateful that folks that know a little (including me, I suppose) put out identification guides based on snapshot photos.
So an interested arborist encounters 1 & 2 and figures that he or she needs to make the identification call or that folks who spread 1 & 2 out over the airways could make the call for them. I play into that some (and probably will continue on the easy ones).

What doesn't get as broad a play, except as a source of frustration to the enthusiast, is that species concepts and macro-ID features for some of our common decay fungi are not so easily recognized. See one fresh sulfur shelf bracket identified in front of you and you are likely to not mis-identify it ever again. But many are not so easily dealt with as in the various posts above, even by experts. But without some pretty intense teaching and learning, one doesn't know what's an easy call and what is a complex one. The Chris Luley book is good as far as it goes, which is probably far enough for its purpose.
And this is a moving front. That sulfur shelf has or will soon have a new species name because it is not the same species as the type for Laetiporus sulphureus from Europe. The Biscognauxia nummularia, which is the one that causes a nasty canker on beech, I was first taught by the learned as Hypoxylon nummularium. That actually is a reasonable transfer, but justification for that is beyond our scope here now.
I guess what pushed me over the edge was seeing several very different fungi sort of being equated because both were lying sort of flat on the stem, while they are biologically as different as...birds and butterflies, perhaps?
JD, I commend your interest! Learn what you can from what you encounter, here and elsewhere!

 

[JD3000]

No worries Kevin. Didnt bother me.

I was also posting some things Ive seen and read about to show the similarities and difficulty of field diagnosis. Original discusion involved difficulty of nailing down an ID from photos and field observation so your points are all right on.
I have been strong for sometime with foliar pathogens, abiotic disorders, insects and mites, and to a lesser extent, common wilts, cankers and some rots. Been diving in to more intensive study of decay organisms.
Fungal Decay Strategies book has been a great purchase as well as finding some great downloadable sources and websites.
As previously mentioned by others, changes in nomenclature have certainly added to the confusion. See all the various "Hypoxylon" diseases out there. Keep plugging away.

 

[mrtree]

Kevin is right that we cannot use photos alone, and mycology is a constant moving mass. Further a little knowledge can be dangerous.

I recently found a sulphur shelf that I have never seen. Causing brown decay, but none the less ID is important if you are acting in a consulting capacity.

What about oxyporous? Is the species we call populinus really the same as the European species?

 

[mrtree]

Read Schwarze's work decide how important ID I and how important understanding fungal host interactions are