My understanding is that in the 19th century European Hornets (Vespa crabro) were accidentally brought here and those are our biggest hornet, but Japanese Hornets/Vespa mandarinia japonica (the huge bee killers) are NOT in the USA, nor any of the Asian Hornet subspecies of Vespa mandarinia.
So this woman whose husband died while mowing his lawn last month in North Carolina was mistaken in calling them Japanese hornets (or "Japanese" is the local NC term for European hornets (crabro))???
Or do we now have them in NC??? (I doubt but want to hear confirmation by someone who knows.)
I heard that an Asian wasp species is a new arrival here and that was confused for Japanese Hornets/Vespa mandarinia japonica (not by size or bee killing just that its Asian.)
I'm pretty sure people have been watching to much nature shows and love to think what they see is a bird sized hornet ready to come eat all their bees so I think she was using the non-proper name for the species, but as she recently lost her husband I didn't want to point it out to her.