Possible Invasion of Imported Willow Leaf Beetle  (two photos)
Plagiodera versicolora

willow leaf beetles
Helen Howard emailed me last fall with these two photographs of thousands of shiny black beetles that were
eating willow leaves along the Green River.
  The other photos show some of the damage caused by both
the larvae and the adults. © Helen Howard, 2014

shiny black beetles
She wrote in her first email:  "I am looking for an ID of these beetles I found on the Green River between
Ruby Ranch and the confluence and on the Colorado River below that this year between September 22 and
October 3rd.  They are 1/4 to 1/2 inch in length, fly, are usually found on young willows and on new growth on
older willows and occasionally on other nearby plants but most commonly on the willows. One landed on me
and bit me- more a taste than anything serious -I had no reaction to it. I paddle the Green frequently and have
for 30 years and do not recall ever seeing anything like this before."  The University of Wisconsin has some
extensive information on their biology and how they arrived in the U. S.  I'm no expert on insects, but I
believe that this may be the Willow Leaf Beetle, based on all the information I've read.  If anyone has
information to the contrary, please email me. Hopefully this year Helen will get a closeup
of these little pests. © Helen Howard 2014

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