By: Sherie Caffey, Horticulture Agent, CSU Extension-Pueblo County
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| Western Yellowjacket |
Most people know that bees are good. There are, however, those who are still afraid of bees, and of course those who are afraid of wasps. Surprisingly, many don’t know the difference between the two. Bees are typically not aggressive whereas wasps are more likely to sting. We have many species of both here in Colorado, and they differ in many ways.
We have many wasp species that are social and form colonies. These colonies are small in the Spring, and grow throughout the summer. Most wasps feed on live insects, and are important in balancing out pests like caterpillars. Western Yellowjackets, however, are scavengers and feed only on dead insects and garbage.
Yellowjackets are often mistaken for honeybees, but they are not hairy and are more intensely colored. They usually nest underground and their colonies are not usually seen. The Western Yellowjacket is the most concerning stinging insect in Colorado. They become a nuisance around outdoor picnics and garbage. It is estimated that 90% of Coloradans who believe they have been stung by a bee, were actually stung by a Yellowjacket.
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| European paper wasp |
If you have seen a papery, open celled wasp nest under your eaves, in your gutters, or even your grill, it is probably the nest of the European Paper Wasp. They are more slender-bodied than the Yellowjackets, but some have very similar coloration. They feed on live insects, many of which are pests. The fact that they nest in many locations around homes has increased the incidents of stings associated with this wasp.
If you have a wasp nest on your property, and it is not causing an immediate issue, the best course of action is to wait until fall or winter, when the nest will be abandoned, and safely remove it then. You can also take a proactive approach by sealing all openings that allow access to hollow tubes or similar spaces. Active nests that are a nuisance can be sprayed with an insecticide labeled for use on wasp nests. Spray the nest during late evening when the wasps are not flying and most foragers have returned home for the night. Excluding food sources such as open garbage cans or pet food will deter Yellowjackets. They also make traps that will attract Yellowjackets, these are best used in June when colonies are still establishing.
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| Honeybee, photo by Lisa Mason |