Plant and Insect Diagnostic Clinic Update - September 16, 2009

The following are highlights and updates about samples and questions received in the Clinic during the past two weeks:


Yellowjacket wasps are STILL causing problems for homeowners as they swarm from holes in the ground or house foundation.  Most callers insist on calling these stinging insects "bees."  Remember, honey bees never nest in the ground.  See the Yellowjacket Wasp Insect Note for more details.

Ugh. Fruit fly calls are on the rise.  By now, large numbers of fruit flies in the house are probably developing in a slow, slimy floor drain, and are not accidental invaders from outside.  Please see our Fruit Fly insect note for tips on how to locate the larval feeding area and eliminate the fly problem.

Now is the time of year that grass spiders become apparent, either as accidental invaders wandering into the house or by their flat, horizontal, sheet-like webs on the grass and shrubbery.  They are harmless.  Vacuum or sweep up invaders and throw them back outside.  See photo below.

There have been more calls on baldfaced hornet nests attached to the house this year than in all previous years combined (or at least as long as we can remember).  See photo below.  We're guessing, but assume the unusual placement of hornet's nest might be related to the rainy weather back in the early summer when queens were establishing new colonies for the summer.  See our Insect Note on hornets.


Grass Sider.  Photo by M. TremblayGrass Sider. Photo by M. Tremblay

Bladfaced Hornet Nest on House.  Photo by Joan Underwood.Bladfaced Hornet Nest on House. Photo by Joan Underwood.


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