Vespula pensylvanica, the western yellowjacket, is a Nearctic species of wasp in the genus Vespula.[1][2] It is native to regions of North America, largely in areas with northern temperate climates. Its reproductive behavior is constrained by cold weather, which successfully reduces the number of western yellowjackets in cold months. However, in the absence of cold weather, this wasp's population can explode. The western yellowjacket has become particularly invasive in the Hawaiian Islands, resulting in their label as a major pest.[3][4]

Vespula squamosa, or the southern yellowjacket, is a social wasp. This species can be identified by its distinctive black and yellow patterning and orange queen.[1] This species is typically found in eastern North America, and its territory extends as far south as Central America.[1] Within these territories, they create enormous, multiple-comb nests.[2] The colonies may be either annual or perennial depending on the climate, and in many perennial nests, polygyny takes place.[3] In addition, this species uses pheromones both as a sexual attractant and an alarm signal.[4] This species feeds on insects and animal carcasses; it does not produce honey.[5] V. squamosa, a social insect, has developed a parasitic relationship with the species V. vidua and V. maculifrons.[2] Due to their painful, venomous stings, the species is considered a pest.[1]

Yellowjacket or yellow jacket is the common name in North America for predatory social wasps of the genera Vespula and Dolichovespula. Members of these genera are known simply as "wasps" in other English-speaking countries. Most of these are black and yellow like the eastern yellowjacket  (Vespula maculifrons) and the aerial yellowjacket (Dolichovespula arenaria); some are black and white like the bald-faced hornet  (Dolichovespula maculata). Some have an abdomen with a red background color instead of black. They can be identified by their distinctive markings, their occurrence only in colonies, and a characteristic, rapid, side-to-side flight pattern prior to landing. All females are capable of stinging. Yellowjackets are important predators of pest insects.[1]

The eastern yellowjacket or eastern yellow jacket (Vespula maculifrons) is a wasp found in eastern North America.[1] Although most of their nests are subterranean, they are often considered a pest due to their nesting in recreational areas and buildings.[2] This yellow jacket is a social insect, living in colonies of hundreds to thousands of individuals.[3] Along with their subfamily, Vespinae, this species demonstrates supportive parental care for offspring, separation of reproductive and sterile castes, and overlapping generations.[4] They aggressively defend their hives from threats and are known to inflict painful stings.