Baldfaced Hornets

These hornets are large black and white yellowjackets that are social.  Their name comes from the fact that they are largely black with mostly white faces.  The classification of hornet comes from its large size and the fact that their nests are aerial. 

Their adults are made up of workers which are sterile females, queens and males which come from unfertilized eggs and they appear in late summer.  Only inseminated females will overwinter in sheltered places like the Yellowjackets do.  She will build her new nest each year made up of chewed up cellulose material.  She will only build the nest to the point of the first brood hatching out and taking over the job of continuing the construction of the nest, which will be about 30 days from the first eggs laid.  This nest consists of layers of cells covered by a many-layered envelope, which protects the nest.  Later in the season there will be larger reproductive cells built where queens and males will be reared.  This is the point where the colony is entering the declining phase.  The newly emerged queens and males will leave the nest and mate; only the inseminated queens will winterover to begin the cycle making a new nest again next year.  The founding queen, the workers and the males will all die.

When the queen emerges from hibernation through the winter she will look for the location for her new nest.  She considers shrubs or vines at ground level to 66 ft or higher in trees.  She also considers overhangs, utility poles, houses, sheds or other structures.  Most locations are constructed in exposed locations.  The nests can grow to 14 inches in diameter and over 24 inches in length.