Plant and Insect Diagnostic Clinic Update - September 28, 2011

The following are highlights and updates about samples and questions recently received in the Plant & Insect Diagnostic Clinic:

 
Diseases

Bur oak tree samples are still coming in! We have diagnosed quite a bit of bur oak blight or as we like to call it: B.O.B.   Urban trees are also being tested for oak and verticillium wilt; however, we have confirmed just one or two cases this year. We suspect that most of these trees are suffering from root damage due to wet weather in 2009 and 2010 and not an infectious disease.

 

We have also seen some more lawn samples with summer patch.  See the ISU Horticulture and Home Pest Newsletter from 7/28/2010 for information and photos about summer patch.

 

Insects

Now is the time we start to notice yellowjacket wasps.  Yellowjacket wasps are the size and shape of honey bees (about 1/2 inch long). Because of the similarity in size and in behavior they are commonly called "bees" by people calling to ask about how to eliminate them from the wall or foundation of the house, the retaining wall or from a hole in the ground. One difference is that yellowjackets are shiny black with bright yellow markings and honey bees are golden brown and fuzzy.  When control is warranted, apply insecticide dust into the nest opening at night.  See our Plant & insect Diagnostic Clinic article for a photo and for details about yellowjacket life cycle and control.

 

Something biting you outdoors that is too tiny to see clearly?  Check out information on the minute pirate bugs on our website.  These beneficial predators get hungry in the fall and occasionally puncture human skin to see if you are a food source.  Fortunately, you are not.

 

The insidious flower bug is a common member of the minute pirate bug group.

The insidious flower bug is a common member of the minute pirate bug group.

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