This video from the USA says about itself:
25 August 2016
Large Bald Faced Hornet nest in a tree with some nice bird calls in the background. These are dangerous hornets and they typically build their nests in trees in the wild and near houses so if one accidentally disturbs them while mowing or trimming trees you won’t outrun them. The worker hornets here are diligently making the nest even bigger. When found away from any human habitation like this nest it’s best just to leave them alone as they are in fact quite beneficial by preying on other harmful insects – all in the balance of Nature. Interestingly, if you are quiet you can film them quite closely as here with a cell phone – they have guard hornets posted who are always on the lookout for anything threatening so best to give these nests a wide berth.
Dolichovespula maculata is a eusocial wasp of the cosmopolitan family Vespidae. Its colloquial names include the bald-faced hornet, bald hornet, white-faced hornet, white-tailed hornet, blackjacket, and bull wasp.