Oh, a wasp? I watched the hole from the minute I saw the back end of the insect looking in the hole (photos 1 and 5), until the head came out. Do you think there are two wasps in the nest? I've been reading your really helpful book for the differences between flies and bees - now I'll go back to wasp and bee differences. I understood wasps would have smooth bodies, no hair - but do have bristles? Which is why this is a wasp . . . Thank you!
Lisa, I thought maybe there was two because I could not see the red legs on some of the photos, but you clarified there was just one insect. The legs and bristles look very wasp-like, also the wing venation. I've not seen any bees with red legs like those ones.