If you know where the nest is, you can move around the house without making the hornets nervous see, you can live with a wasp’s nest in the house or garden. In many cases, it is impractical; especially there are children in the house. Then eradication is necessary.
A free-hanging hive can be neutralized by spraying an insecticide containing pyrethrin I and II + piperonyl butoxide into the entrance hole.
The pyrethrins instantly confuse and paralyze the hornets and prevent them from using their alarm signals. Dusting the nest entrance with insect powder, so that the hornets will get a little powder on them when entering and exiting the nest is also effective. If the nest is hidden in a hole in the ground or in a cavity wall, applying insect powder on the entrance will have to do. The treatment is repeated a few days in a row until the traffic in and out the hole ceases.
Unlike honey bees, hornets’ colonies only last for one year. In October-November, the nests are empty and it is safe to remove them – or let them hang – they are never reused.
Light traps that attract hornets using ultraviolet light and capture or kill them, can help hornet problems in bakeries and other food firms.