I did my first bee removal from an old shed. A neighbor said the bees have been there since he was a kid (He's about 40).The comb was built between the studs and completely filled the space from floor to ceiling. There were a lot of bees. I removed the sheetrock from the inside of the shed and exposed the comb. I was only able to remove about half of the comb which has all been relocated to any empty super with a lot of the bees. Most of the brood comb was in the lower half. I don't think I got the queen. I am going back to remove the rest of the comb and the bees. The owner wants to know if there is anything natural or organic that could be sprayed on the empty space to prevent any stray bees or stragglers from returning and building anew. Any thoughts or ideas?

Also there was another entrance that a small number of bees were going into about 4 feet away. There was no connection with the comb I was removing. A completely separate hive? Another queen?