DH has kept bees for about 25 years, running as many as 500 hives in Utah years ago. It's fair to assume he knows his stuff fairly well. Yesterday we had a hive swarm into a small nearby tree. DH took a box and went up to the hanging swarm to catch it. He rarely dresses for the occassion, and ususally he can pick up the swarm and not get stung once. This time, he proceeded to attempt to lightly knock it into the box. Those bees went crazy! It's like they weren't in swarm mode at all. He got stung at least 30 times. (we scraped 30 stingers out of him) He is sore and still rather swollen today on his face and his right arm. This is the worst he's been stung in all his years of beekeeping. Any of you ever have experience with an aggressive swarm? This is our first really aggressive swarm. We did manage to catch them, and they seem to have settled into their new hive. What makes a swarm aggressive rather then gentle, as most swarms are? Thanks in advance.