Insects and Spiders - native

Pine sawfly (Neodiprion sp.) on Jun 28, 2019

Originally reported as Unknown insect or spider

Submitter does not have a specimen
EDRR Status: Local expert notified

Description of specimen

Trees are brown within 2 weeks
Lot of seeping
Worms falling from trees
Black head green body worm June 7, 2019 June 20, 2019


Looks like pine sawfly, Neodiprion sp.

Wyatt Williams
June 28, 2019, 9:42 a.m.

Looks like pine sawfly. Thanks for logging the report and taking good photos. Forest entomologists have been notified and awaiting confirmation. If it is pine sawfly, the damage is quite apparent and looks pretty severe. However, outbreaks of this native insect are short (1-2 years) with little to no tree mortality. I will update this thread when the identity is confirmed

Wyatt Williams
June 28, 2019, 9:45 a.m.

Follow up from Dr. Robbie Flowers, USFS entomologist, Bend OR. Robbie's field report: "Just a follow-up on the pine sawfly defoliation ground checks. It seems to be mostly centered along highway 97 east of Crater Lake and extends from just south of the Crater Lake cut-off (highway 138) to the southern entrance of Silver Lake Highway (highway 676) by Sand Creek Station.

"It seems to be largely restricted to lodgepole pine occurring within a mile or so of the highway corridor. The defoliation was highly variable, with light to severe defoliation often occurring within the same stand as is common to these type of pine sawflies (see attached pics). The new foliage is just beginning to flush, and as many of the red/fed-on needles often break-off, it may look quite different over the next few weeks."

Wyatt Williams
July 10, 2019, 2:15 p.m.

Sawfly outbreaks are often infrequent, short and collapse on their own but can be damaging. Here are some resources to read:

Wyatt Williams
July 10, 2019, 2:21 p.m.