Hornets are the largest eusocial wasps, that reach up to 45 millimeters (1.8 inches) in length. The true hornets make up the genus Vespa, and are distinguished from other vespines by the width of the vertex (part of the head behind the eyes), which is proportionally larger in Vespa; and by the anteriorly rounded gasters (the section of the abdomen behind the wasp waist).
A hornet's sting is painful to humans, but the sting toxicity varies greatly by hornet species. Some deliver just a typical insect sting, while others are among the most venomous known insects. Allergic reactions, fatal in severe cases, can occur an individual suffering from anaphylactic shock may die unless treated immediately via epinephrine ("adrenaline") injection using a device such as an EpiPen, with prompt followup treatment in a hospital.
If you're concerned that you have hornets nesting near your home or place of business, give Dave a call at 1-800-400-6009.
Dave's Pest Control
Serving Central Massachusetts