I agree with that. I couldn't think of an approach that had a chance of victory. If anything I'd like to avoid kicking the wasps neat here if at all possible, considering their size and numbers. But if we could isolate their queen then they would be at our mercy.

Wait. The underground tunnel is a good idea, but even then we would have to climb the tree to launch any sort of attack. We'd be left exposed enough doing that that there's no way our surprise would last and we'd be stuck fighting an aerial foe while clinging to the side of the tree. But what if we could completely negate their ability to fly?

What if we attack while it's raining?

We've seen the rain, it's almost suicide to be caught out in it. Especially flying. No one would expect to be attacked during that. Those waterproof shelters I proposed? We could rework that idea into something we could carry with us up the side of the tree to protect us from the rain and use the sound to mask the noise our approch. I'm picturing a squad of soldiers and workers. The soldiers to take on any of the wasps that try climbing out to fight us, but the workers are more important here. Once we're up the tree we have them start sealing off exits from their hive with the sticky fluid they have. Funnal the wasps to, ideally, a single exit where we can pick them off. Hell, maybe seal them in entirely and cart the whole thing to the river.