I've also recently learned about Sudden Oak Death, a fungus which is ravaging forests in California and Oregon. Evidently it is unknown where it came from.
Besides the famous case of the chestnut:
Dogwoods are being wiped out, mostly gone in some areas, disease originating from Asia: https://henderson.ces.ncsu.edu/2021/03/native-dogwoods-long-...
Sassafras trees wiped out by Asian beetle causing laurel wilt: https://www.lsuagcenter.com/articles/page1685633928383
American elms largely wiped out by Dutch elm disease (also actually originates from Asia) https://www.invasivespeciesinfo.gov/terrestrial/pathogens-an...
Others in this thread have talked about the threats to ash. It's very disheartening, but I guess it's the inevitable price of globalization.
Being from the US, I don't recall any such stories in the news.
Most of these are from Asia and Noth America.