Should have been able to do it 20 feet away with Wasp&Hornet killer. I swept a can of that side to side in a 1ft wide section of a bush in Florida where I saw a Hornet fly in. After a good two second sweeping spray one fell out.. and then several more fell out. I swear by the stuff; it works great!
On a related note, I tried to use some of that as a flamethrower to kill "banana spiders" in Korea, but the spray was strong and would not light. The fine mist of OFF! spray would ignite however. We sprayed a fireball from that, and then sprayed wasp&hornet killer through the flame and MAN, THAT worked! I bet it would have done an amazing job on that bee nest, and a "windproof lighter/crack-torch" would probably do well for ignition.
You didn't get this idea from me, though.