Life Cycle: Females will live over winter while males and unfertilized wasps will die. In the spring, potential queens compete for control over a nest by attempting to lay more eggs than the other. After a short competition, one queen will dominate the nest.
Behaviour: Umbrella wasps are much more docile than other wasps, they rarely sting unless the nest is disturbed. These wasps feed on insect larvae and rotten fruit, and are thus more of a pest in orchards or near fruit trees.
Signs of Infestation: The nest itself is a single layer of cells with no covering and is suspended from a stalk. They build inverted, exposed cell, umbrella-like under eaves and in old buildings.