It's unusual to have colonies situated as close as these ones have been and they won't remain like this for long. The reason for having them so close together is so that, when I move each 'parent' colony away from the 'swarm' colony next door to it, all the flying bees will easily find the swarm colony and relocate to it. Their navigational skills are very precise and they may be unable to find their way to the entrance if it is more than 3 feet from where they expect it to be!
I'll be relocating the first of these colonies tomorrow and, as it will be a new permanent site for a colony I spent some time digging some footings for it - nothing too complicated, just some slabs over some buried sheeting to keep the weeds down. I've found it hard to keep on top of the weeds right next to the hives - the bees detest the scent of freshly-cut weeds just as much as the scent of soil being dug!
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