Plant and Insect Diagnostic Clinic Update - June 29, 2011

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

 
Insects

 
Millions of Migrating Millipedes Maraud the Midwest! We don't have anything new about millipedes to add to the Update from June 14, 2011, other than to say, "Yep.  They are still out there." See the pictures below for how bad it can get!


Calls and messages continue to describe hoards of millipedes in the lawns, on the driveway and patio, on the side of the house and indoors.  The common question is, "When will they leave us alone?"  The short answer is, "We don't know, but hang in there."  In the meantime, like we said last issue, "There still is no silver bullet for millipede prevention.  Perimeter barriers of insecticide around the house or other building must be very large to accomplish any protection.  None of our residual insecticides kill millipedes quickly enough to "drop them in their tracks" after crossing an insecticide barrier of only a few inches next to the house.  See our website more more details.


The first report of Japanese beetles this year came on June 22.  There has been a steady tickle of calls and messages since then, but that should change to a torrent as we reach the peak of adult emergence in mid-July.  See the article elsewhere in this issue.


It's the time of the year to see dobsonflies.  These huge, prehistoric-looking insects are unmistakable.  See the Plant & Insect Diagnostic Clinic article for details and photos.


Disease


We continue to receive lots of spruce with Rhizosphaera needle cast and stigmina needle cast


Ornamental plants with root rots are starting to trickle in as well.  Although there are several fungi that can cause root rots right now we are mostly seeing pythium


Female dobsonfly.  Males have 1-inch long, curved, slender mandibles.


Female dobsonfly. Males have 1-inch long, curved, slender mandibles.


 


 



 


 



Garden millipedes migrating by the thousands.  Photo courtesy of Steve Harvey.

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