A New Paper City Every Year

My son and I took a walk around the backyard to check on the progress of our paper-nest-building neighbors, thousands of Baldfaced Hornets (Dolichovespula maculata) They're actually wasps--not real hornets, related to yellow-jackets, and they build these absolutely beautiful homes of paper, a new one every year. 

The nest is at the base of a small tree a couple hundred feet from the house.  Apparently these guys are aggressive, but my son and I got within a foot or two of the nest, taking pics, and they didn't seem to care.