Thanks Claire
I've heard about this idea but hadn't quite figured out how to make it work. Also, he mentions spraying a tree with anise oil and sugar water. The famous bee research, Tom Seeley, believed anise oil was the best way to attract bees to sugar water for his testing. I got some at Freddy's last week.
Hope you enjoy this.
https://www.youtube.com/watch?v=5iPA3IZSPmE
I wouldn't recommend sitting through all 15 minutes of this one but it is an interesting idea if you know your own bees are about to swarm.
https://www.youtube.com/watch?v=jvlZ5gvGc0Q