Introduced European Saw Flies in Washington???

Please help us if you can!
I live in a condo association. Today we discovered these insects in several of our small pine cone bushes. There are hundreds and hundreds of them in all the bushes. If you could identify this caterpillar or worm I would VERY much appreciate it. Most of them are totally black and smoth and slimy like a snake and about 1 inch in length. Here is a picture: Looking forward to a reply at your earliest convenience! Thank you so much!
Gail Phillips
Bellingham, Washington

Hi Gail,
We believe you need to contact your local Department of Agriculture Insect Pest Control division. Call 360-902-2070 or email [email protected] because we believe you have the Introduced European Saw Fly, Diprion similis. This introduced species is known in the eastern U.S., but we cannot find any indication that it has become established in Washington. BugGuide reports it as far west as Wisconsin. If you have an isolated outbreak, control might still be possible. The University of Georgia Forest Pests website indicates: “The introduced pine sawfly occurs from Canada to North Carolina, and in the central and lake states. Eastern white pine is its favored host, but it also attacks Scotch, red,jack, and Swiss mountain pines. Infestations of this insect can be very serious in young plantations of white pine grown for timber products or Christmas trees.” Several days ago we received a letter from Michigan regarding this species.

Probable Confirmation: (06/02/2008) Sawfly larvae on Whatcom pines
Hi Gail (and others )
The larvae are likely the European pine sawfly, and yes, the occurrence of the species is the first for Washington State (and Western U.S.). However, the species has been in neighboring British Columbia, Canada, for some time, including areas of the Frasier River delta which is not far from the Bellingham area. Here is a link to information on the B.C. occurrence: I appreciate your interest and efforts to bring the situation to our attention. I am in the process of getting some of the larvae (with help from the County Extension office) to get confirmation of the species and would be glad to let you know if/when that happens. Thanks again for the contact.
Eric LaGasa
Chief Entomologist
Pest Program / Plant Protection Division
Washington State Department of Agriculture
[email protected]

Thanks so much for your Email and information contained therein regarding our occurrence of this recent troubling ‘event’. Yes, we would very much be interested in continuing updates regarding this ‘infestation’. Also, many thanks to for their immediate response to my inquiry in helping to identify this particular species! Sincerely,
Gail Phillips

Ed. Note: The spread of the European Pine Sawfly can be a threat to our Western logging industry as the species is proliferating without natural predators.

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