To protect the air quality for my neighbours' lungs in an urban area, I never have bonfires: prunings and branches are piled up to rot naturally. Common wasps, Vespula vulgaris, are making a nest in there somewhere and one was chewing a dead clipping -- presumably to make new cells from the "paper chewing". They are fascinating insects.
Wasps may be a pain at a BBQ yet they do great work in the ecosystem in controlling caterpillars.
They are not usually aggressive and I was working today up a ladder a meter from this nest site pruning large tree branches. I was no threat to them and they didn't sting me. I was ready to run at any time though!