We live in the middle of a forest. These hornets seem to eat wood, as I have witnessed them stripping wood off of fences. Or perhaps I have the two species, hornets and wasps, confused.
They’re not eating the wood, they’re chewing it up to make their nests. The wood’s still damaged just the same, but they don’t eat it.
I know some wasps strip wood to make a mush that they use to build paper like nests. Bigger black wasps use clay. Not sure what hornets use to build their nests. A hornet is about the size of a thumb while a wasp is half to a third of that depending on the specie in my parts. Both black wasps and hairless hornets hunt spiders in my area. The larger hairy hornets attack cicadas in flight.