Friday, April 8, 2011

Paper Wasps

Sean McCann- Bugguide.net
A sure sign of spring is the appearance of red wasps around our Bull Creek house.  They get into the eaves of the house from spaces around the soffit and find it a great place to raise a family.  They do have annoying neighbors (us) who disturb them by coming in and out of the front door and have expressed their annoyance occasionally quite painfully in the past.  They are said to be "harmless unless disturbed" but we are still negotiating with them over the definition of disturbance.

This winter I carefully caulked all the known openings.  Only the pregnant female queen survives the winter but she becomes very active in the spring.  Already she has produced many worker females who are tending to the next batch of young.  They seem to be hovering around the caulked cracks as though they remember where grandma once lived.  As the summer progresses and more workers are produced, they will be bringing caterpillars back to the nest to deposit with each egg as a food source for the developing larva.  This is considered beneficial to humans if not to the caterpillars.

Wikipedia describes Paper wasps in general and Polistes species at great length.
Paper wasps are 0.75 to 1 inch (1.9 to 2.5 cm)-long wasps that gather fibers from dead wood and plant stems, which they mix with saliva, and use to construct water-resistant nests made of gray or brown papery material.  Paper wasps are also sometimes called umbrella wasps, due to the distinctive design of their nests. 
The nests of most true paper wasps are characterized by having open combs with cells for brood rearing, and a petiole, or constricted stalk, that anchors the nest.  Paper wasps secrete a chemical which repels ants, which they spread around the base of the anchor to prevent the loss of eggs or brood.
Smithsonian Magazine this month describes an interesting behavior of paper wasps.  "Larva turn into either workers or potential queens, depending on the behavior of adults, say University of Wisconsin scientists.  If adults drum on nest walls with their antennae, the vibrations inhibit fat storage and produce workers."  The whole story with a video is at http://www.news.wisc.edu/18877  Note: My mother tried this when I was a teenager by pounding on my door- it didn't work.

Missouri Extension has practical advice dealing with a wide variety of stinging insects.