thanks everyone, it would make sense that the mites are dead if the bees are dead and gone. This nuc was installed in April in southern Indiana, very wet all spring, summer and fall. They never acted right, never built comb, I was feeding them until August and when the golden rod came out I did a wait and see. They were gone except for maybee 50 bees crawling on the bottom on September 15.
I sent those to the Bee Research laboratory via the county bee inspector, the official letter came in the mail.
I think I'll do some housekeeping before the new nuc is installed.