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This species is black with yellow markings. Yellowjacket resemble to Vespula germanica but its face lacks of black spots present in German wasp. The workers sizes oscillate between 12 and 17 mm, queens 15 to 20 mm. Head: malar space less than half as long as penultimate antennal segment; occipital carina incomplete, it reach mandible base; workers with a black mark behind the eyes; wide black stripe between the corona and ocular sinus. Mesosoma: yellow pronotal bands parallel. Metasoma: apex of seventh tergite of male depressed, shaft of aedeagus with a acute tooth of each side to base of terminal spoon (Miller 1961). Xanthic workers rarely with evanescent enclosed yellow spots on tergum 2 (Buck et al. 2008)

The Yellowjacket is a social species with annual or perennial colonies. In early May the queens looking for nesting places, they start the nest underground or in hollows of trees or wall buildings. Sometimes the nests are aerial (Akre et al. 1981, Buck et al. 2008, Kweskin 1997). The queen adds cells inside the nest, she lays eggs (one by cell), the larval hatches in 5 or 8 days and the queen takes care of the larvae, after 5 molts the larvae spin a silk cap and pupate. The first workers emerge in early June and the queen doesn’t leave the nest again. The workers search food and fibers, care the larvae, clean the cells, feed the queen, the larvae and the males, they exhibit trophallaxis, mauling and ovoposition behavior, and also they protect the colony. The mature nests eventually have more than 1000 workers; if the colony is disturbed they defend the nest aggressively. The new queens and males are produced in late September. The annual colonies decline in late October (Akre et al. 1981, Buck et al. 2008).

They feed regularly on live prey but they also have affinity to scavenge on carrion. They are mostly predators of spiders, harvestmen, caterpillars, flies, hemipterans, soft beetles, butterflies, crickets and other bugs. The adults carry their prey or part of them to the nest to feed their larval states. They also feed of flower nectar or sweet substances as aphid honeydew (Akre et al. 1981, Buck et al. 2008).

The Yellowjacket is a Holarctic species with transcontinental distribution in Neartic region, this species is found in North and Centre America, Europe and Asia (Miller 1961). This species was introduced species to Hawaii, Iceland, New Zealand and Australia (Carpenter & Kojima, Kweskin 2000, Rodriguez-Palafox 1996). Canada: all provinces and territory less Nunavut. United States: Northern and western. Mexico: Ciudad de Mexico, Durango, Michoacan and Oaxaca (Buck et al.1981).

Yellowjacket has been nominated as among 100 of the “World’s Worst” species invaders. In places where the Yellowjacket is an introduced species it affects negatively the beneficial insect fauna and it generates economical lost in crops (Kweskin 2000).