Sorry for not posting in a timely fashion. We've been very busy with harvests and bees.
Below is our fourth colony, now termed the duplex. Two days after the second swarm showed up, a third (also from the neighbors or a feral colony) appeared in our blackberries. That's three swarms in 10 days landing within 30' of one another. I think we're in a sweet spot for bees!
We dithered for a few days on what to do; we had very little extra bee hardware on hand. After the swarm stayed put two nights in the berry bushes, and with a forecast of thunderstorms moving in, we decided to try combining this swarm with the second swarm. We hit the bee text book and got the details on using newspaper to temporarily screen the two colonies from one another. A lot of beekeeping theory has become practice for us in a hurry!
This is a shot of the duplex with the newspaper in place. The bees chewed through it in about two days. We later inspected the hive and found the surviving queen. We named her Calamity Jane, and marked her as an '08 queen (red). (She might be older, but there's no way to know.) The race is on: these bees need to quickly lay in 60+ pounds of honey or they will not survive the winter. We're helping with sugar syrup feedings; they are sucking down a pint+ a day. There are plenty of things in bloom and the weather has been perfect, so they might make it.