THE WIND HAS BEEN STRONG the past few days, shaking down leaves, pine needles, and other materials. On a back road in a bare tree was quite a find, a huge paper wasp nest of the common bald-faced hornet. They are not really hornets, but a type of wasp called Dolichovespula maculata. This wasp is black with bonze wings, and the face is white with black eyes. There are a few white bands on the abdomen, and it is quite pretty.
The nest had enough weight to bend the branch down to a level where it was visible. At first it appeared that leaves had been driven into the outside of the nest. On closer inspection (with binoculars) the nest had been constructed around the leaves of the branch and some were still alive and attached inside to the branch. The hornets had very securely anchored their nest to this rather thin branch.
The shape of the nest is interesting because the design keeps the water out and forces it off the outside layers. The entrance/exit hole is near the bottom. A queen bald-faced hornet that has overwintered makes the paper nest in spring (April to May) and constructs it from wood, bark and other vegetation and her saliva. Then several cells are made, and an egg laid in each to start the new colony of sterile female workers for the season.
The hornet cells are made in circles on horizontal layers and the queen uses her saliva to smooth out the paper into a “carton.” The size of the colony and the nest keep growing throughout the season, and the structure can be over a foot in length and almost as wide. Typically, there are 200-300 hornets in the nest, and over 500 have been found in some.
Compared to yellow jackets they seem to have a more docile personality if the nest is not disturbed. If the nest’s thin outer layers are damaged, there is an instant attack on the assailant and multiple stings can be given by each hornet. This should be avoided because the venom can cause anaphylactic shock, and if you are pursued, one expert advises to “run like hell.” This accomplishes the hornets’ goal, and they stop stinging.
In the fall fertile males and new queens have been produced which mate and the queens go out of the nest to find shelter behind tree bark for the winter. All the hornets except the queens die. The nest may remain on the limb for quite some time and is a temptation to cut down and save. My grandfather saved a huge one from the yard maple trees one year and it was hung up in the cold woodshed for all the grandchildren to admire. A librarian friend had one brought in as a curiosity to display on one of the library tables along with some pumpkins. Unfortunately, the warm room revived a few lingering hornets which emerged onto the table. They were quickly killed before any library patrons were stung. This is a cautionary tale to keep the nests outdoors and sheltered to be sure there is no life left inside. It is recommended that removal and extermination be left to professional exterminators. As the leaves fall and trees become bare, many of these beautiful nests can be seen. If you want to examine one, wait for a cold day and take it apart outdoors. The construction ability of these insects is truly amazing.