I have a friend who has a colony of bees take up lodging in the recesses of a large banyan tree here in Southern Florida. The tree is too old and valuable to start hacking or sawing into it to remove the hive and there are multiple entries for the bees to come and go. The aim is to simply euthanize the bees. What is the best way to accomplish this task. The bees are not africanized and the hive is still relatively small given the time they have been there. I have been advised that soapy water will drown them. Thank you for your feedback.