Some bumblebees are more aggressive than others. If what your friend wants to knowis, will they attack him, then he could find out by slowly approahcing the nest and seeing if the bees notice him or not. That would give him an idea as to how nervous he ought to be regarding their proximity to his house. Foraging bees almost never sting - it's being near the nest he should worry about. Good luck Liz Day presently in New York City, USA receiving mail at [log in to unmask] (that's Lday, not ONEday)