With spring just starting, I guess thoughts are now turning to possible early swarming. As I live in an urban environment I would like to be able to have some awareness of when/if my hive is likely to swarm so that I can warn my neighbours.
How can I tell, without opening the hive how close to swarming they are? Any details would be helpful as this is a source of some concern to me. Many thanks
Graham, Reading Berkshire