Neil,
when living in SW France had a Asiatic hornets nest in a tall tree…….
big hanging thing, also a thing of wonder……about a meter long and almost as big around…..
the local council refused to touch it because it was so big……
Had to kill em myself, which involed over 12m of 3/4 copper pipe, 1/2 lit petrol and an air compressor…….
AND for the interested few…..no I didnt BURN them out…….
Petrol fumes will kill them almost instantley……
when keeping honey bee's in the UK, worked with someone from the Ministry of Agri……
when bee's had a notifiable disease the bees were trapped inside and killed with a cup of petrol…..
then the hive was moved and burnt (in a safe place)…