How can a get rid of bees that have ';nested'; inside the top of the pole of my patio umbrella?

We can not use our umbrella because if we open or close it the bees come out and attack? Can bees drown? We thought of removing the umbrella and immersing it in the lake. Help!How can a get rid of bees that have ';nested'; inside the top of the pole of my patio umbrella?
ortho makes a wasp/hornet spray that comes out in a foam. i had wasps nesting inside my mailbox pole, i sprayed the foam thru the little hole in the side of the pole and filled that ****** up to the brim with foam. they haven't been back since.How can a get rid of bees that have ';nested'; inside the top of the pole of my patio umbrella?
use a spray called ';Home Defence'; it not only kills but keeps them away for a year. Once you get rid of them spray the umbrella at the start of the spring
Bee-lieve it or not,dishwashing soap (manual one/liquid) or if you have Chlorox, pour this in and wait 30 minutes then spray the pole-hole with water from your hose. I sprayed a wasp nest that grew in the passenger door of my car with just a cleaning spray (I think it was Chlorox or Pine-o-sol). Or just spray with Raid for bees/wasps. Bee careful.
That's actually your best bet if you don't want to use spays. Take some landscape fabric and tie off the top and bottom. Do this in the early morning before they come out. If you're lake front than submerge the entire pole for a while. They breath air, they can drown. If you're not, than submerse it in a pool or flush with a hose. To stop this next year, take some thing and either plug or cover the hole. You can also spray the umbrella in early spring to prevent nesting.
Tell them to bee-have or you will spray them with one of the many products available for the purpose of killing nasty flying stingy things
Wrap layers of outdoor fabric (or pieces of tarp) over the top and secure it tightly with both twine and glue, so they can not get in or out. Or, get some spray-in insulation foam and fill the inside with foam. Just make sure you don't hinder the umbrella's operation (i.e. can still open and close it.)