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Dogwood sawfly

Macremphytus tarsatus

23 host plants

Last updated

Data Coverage 2 of 6 dimensions
Host Plants
GDD Threshold
Peak Activity
Damage Severity
Monitoring
Regional Notes

Dogwood sawfly larvae feed on dogwood foliage, creating skeletonized areas where they consume leaf tissue while leaving veins intact. You will see lacy, brown-looking leaves that may eventually drop. Damage appears in early summer as larvae move through new growth. Cornus species including Cornelian cherry and kousa dogwood are affected. Infested trees look unsightly but usually recover as they push new growth.

Monitor new foliage regularly starting in late spring for the first appearance of skeletonization. Prune out lightly infested branches and remove them from the site. Bacillus thuringiensis (Bt) applied early when you see young larvae feeds on leaf tissue with minimal impact on beneficial insects. Most dogwoods tolerate leaf loss without serious harm. Allow natural parasitoid populations to establish; they provide effective control over time without intervention.

Quick Reference

Order
Hymenoptera
Type
defoliator
Host Plants
23
GDD₃₂ Larva early instar
3,229
Indicator: Japanese stewartia first bloom

Dogwood sawfly Larva early instar typically begins around 3229 GDD₃₂. As of April 12, 2026, Puget Sound stations range from 1235.8 to 1375.3 GDD₃₂, approximately 1854 units before the expected threshold.

Regional Season Tracker

GDD₃₂ accumulation across 7 Puget Sound stations · as of Apr 12, 2026
Station GDD₃₂ Current Stage Next To Go
Issaquah / East King 1,375 Pre-season Larva early instar 1,854
Seattle / UW 1,348 Pre-season Larva early instar 1,881
Kent / Auburn 1,308 Pre-season Larva early instar 1,921
Olympia / Tumwater 1,292 Pre-season Larva early instar 1,937
Bellingham / Whatcom 1,270 Pre-season Larva early instar 1,959
Tacoma / Puyallup 1,258 Pre-season Larva early instar 1,971
Sequim / Rain Shadow 1,236 Pre-season Larva early instar 1,993

Source: UMD IPMnet catalog. Sources: UMD: extension.umd.edu. About GDD₃₂ →

Host Plants (23)