(Editor's Note: This article was originally published on June 17, 2009. Your comments are welcome, but please be aware that authors of previously published articles may not be able to promptly respond to new questions or comments.)
One of the most common questions asked on forums where bees and beekeeping are discussed is how to get eradicate a bee colony on someone's property. This is wrong in two ways: First, because bees are valuable pollinators that deserve human protection and are not normally aggressive. In the unusual event that a honeybee colony is endangering human beings, perhaps someone who is allergic to their stings, a beekeeper may be able to remove it without harming the bees.
But it is far more likely that the troublesome nest actually holds yellow jackets, not bees. Unfortunately, the aggressive behavior of these wasps has given a bad reputation to their distant relatives, the bees, with whom they are often confused. For the sake of the bees and for safety's sake, it is important to learn the difference.
It is not a coincidence that bees and yellow jackets bear some resemblance to each other. Bees evolved from primitive wasps over a hundred million years ago. In addition, many species of both bees and wasps are social, dwelling together in large colonies where a queen produces eggs that are tended and fed by sterile females. This is the case with both honeybees (Apis mellifera) and yellow jackets (Vespula species), which leads many people to confuse them.
"Yellow jacket" is not a scientific term. I am using it in this article to refer to the members of the genus Vespula that have black and yellow coloration, with bands of black and yellow on the abdomen. These are the wasps most commonly misidentified as bees.
There are several species of yellow jackets, which all resemble each other rather closely. The Western Yellow Jacket (V. maculifrons) and the Eastern Yellow Jacket (V. pensylvanica) are native to North America. The German Wasp (V. germanica) and Common Wasp (V. vulgaris) are native to Europe but have now spread worldwide. They are distinguished by the different patterns of yellow and black on their faces and abdomens, but as individuals vary, it is difficult to distinguish members of the different species without close examination.
Most species of yellow jackets have similar habits. They are social wasps that live in large colonies of several thousand individuals. The queen mates in late summer and overwinters before seeking out a nest site in the spring, where she constructs papery egg cells from chewed wood pulp. Yellow jackets commonly nest underground, but they may also colonize cavities and crevices. Unlike other paper wasps, their nests are not out in the open.
The queen raises the first few dozen workers by herself; once these are mature, they tend the subsequent broods of larvae. The yellow jacket larvae, like those of most wasps, are carnivorous. The workers feed insects to the larvae, which exude a sugary substance consumed by the workers. By autumn, the activity in the yellow jacket nest is at its height, as the queen lays the eggs for the next generation of queens and their mates. However, once the queen ceases laying eggs, there are no longer larvae in the nest to produce the sugary exudate for the workers, who then seek out sugary substances, such as rotting fruit in orchards. With the coming of winter and freezing weather, the wasps die off, except for the newly-mated new generation of queens.
Yellow jackets are not important pollinators, although they may occasionally visit flowers for nectar. They do make a valuable contribution to the gardener by preying on other insects. However, their aggressive behavior in defense of their nests, particularly in the early autumn, makes many people consider them more of a nuisance or a danger than a benefit. Several dozen people a year are killed by yellow jacket stings in the US alone; most of these deaths are the result of allergies, but sometimes individuals who blunder into a yellow jacket nest can receive hundreds of stings, enough toxin to kill a person.
Because honeybees also live in large colonies and are approximately the same size as the yellow jackets, they are most often mistaken for them. But while there are many species of ground-dwelling bees, honeybees do not like to make their nests in the ground, as yellow jackets most often do. They are cavity nesters and prefer a location such as a hollow tree, off the ground. Sometimes, however, as yellow jackets also will, they find their way into the exterior walls of a human building. Honeybees, even the Africanized bees, are relatively unaggressive, certainly as compared to yellow jackets.
Honeybees may remain in the same location for several years. Because much of the colony overwinters, it is most active in late spring, when yellow jackets are only beginning to make their nests. It is in spring that honeybees are most likely to swarm, searching for a new location for a nest.
Yellow jacket (European wasp)
From the images above, it is easy to distinguish between the wasp and the bee. The yellow jacket's coloring is black and bright yellow in a strongly defined pattern. The honeybee is more of a bronze or amber color, with stripes less clearly defined. The yellow jacket's body is smooth, almost hairless, while the honeybee is very fuzzy in order to trap pollen on its body. The yellow jacket's legs are yellow and thin. The honeybee's legs are black, and the rear pair thicker to form a pollen basket. The yellow jacket's wasp waist is noticeably thinner than the bee's; its abdomen is generally longer and more tapered than the bee's.
If you see a large number of buzzing insects moving in and out of a nesting cavity, take a good look (from a safe distance) to make sure what kind of a nest you have: yellow jacket or bee. Don't make the bees pay for the yellow jacket's vicious reputation.
Yellow jacket (V vulgaris) thanks to Laurie Gray Bounsall from BugFiles
Yellow jacket (European wasp) and honeybee by Fir0002/Flagstaffotos. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 only as published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled "Text of the GNU Free Documentation License."