Hornets - Advice for identifying and controlling

What do they look like?

Queens (reproductive females) are larger than males and workers (non-reproductive females).  The head features large, c-shaped eyes, robust antennae and three simple eyes or 'ocelli' arranged in a triangle between the main eyes.  The thorax and abdomen are separated by a distinct 'wasp-waist', and there are alternating bright orange-yellow and brownish-black stripes along the abdomen.  There are two pairs of wings, which are joined together by means of tiny hooks, giving the appearance that there is just one pair of wings.  Hornets are twice the size of the common wasp.

How do you spot them?

Hornets nest in hollow trees, wall cavities, chimneys and similar structures, and show a preference for wooded areas.

The Life Cycle

Queens emerge from hibernation during the spring, and searches for a suitable location in which to start a new nest.  She begins to build the nest with chewed wood pulp, and a few eggs are laid in individual paper cells; these eggs develop into non-reproductive workers.  When 5-10 workers have emerged, they take over the care of the nest, and the rest of queen's life is devoted solely to egg laying.  Hornet workers capture insects, bringing them back to the nest to feed the brood.  Workers need more high-energy sugary foods such as sap and nectar, and hornet larvae are able to exude a sugary liquid which the workers can feed on.

The nest grows throughout the summer, reaching its peak size towards mid September.  At this time the queen lays eggs that develop into males (drones) and new queens and she dies shortly after.  The new queens and males mate during a 'nuptial flight', after which the males die, and the newly mated queens seek out suitable places in which to hibernate. The old nest is never re-used.

How do you control them?

Hornets are generally peaceful and non-agressive.  If the presence of a nest is causing no direct problems, it is best to leave it alone as hornets control many species of insect pests. However, should it prove necessary to destroy a nest, please seek the help of a professional pest control company.

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