I was thinking we should first deal with whether we should do this before muddying the waters with discussing specific names, but didn’t actually expect that to happen. So let the name games begin!
First let me say thank you to John for a good belly laugh at his names, followed by chuckles later as they came back to me. My idea for the disease caused by H. occidentale was “western root disease”. I think Otrosina and Garbelotto made a good choice of a specific epithet there, because ‘occidentale’ indicates that it is the disease that is restricted to the western portion of the continent. This is an important feature that is worth noting in the disease name. That said, “hollow root disease” is also good. It certainly is a memorable feature in fir stumps (although I vaguely recall, and probably have in my files, an old paper in a southeastern forestry publication with a title something like “Fomes annosus is hazardous to your health”, because the pine stumps and roots are hollowed out, causing a tripping hazard). I’m not sure I would put ‘fir’ in the disease name, since in some areas it is most notable on hemlock, or Douglas-fir, or spruce.
As for the disease caused by H. irregulare, it is important in the West also, and has become more important in the Midwest. It also occurs in the Northeast, southern Canada, and Mexico. So unless it causes a distinctly different disease in southern pines than in the other areas, I’m not sure it is good to focus on southern pines for the disease name. For it I thought of “pine stump disease”, but would not be surprised if a better name could be found. Maybe a translation of “maladie du rond”?