(Question)
Pine tree in upper beaches in a small garden.
Branches being stripped.
(Answer)
Thanks for contacting Toronto Master Gardeners. The closest match to your picture is a Choristoneura pinus Freeman, the jack pine budworm, which is a moth of the family Tortricidae. They can cause widespread defoliation and eventually lead to tree mortality. The larva emerges from under bark scales and late May or early June. They leave partially-chewed needles and accumulated spun silk. During severe outbreaks, the bacterial spray Bacillus thuringiensis kurstaki (Btk) can be applied.
Tips for best results:
- Do not apply the first spray until all caterpillars in the area have hatched.
- Limit spraying to the infested area.
- Apply Btk late in the day to avoid intense sunshine, which breaks it down.
- Apply Btk when winds are relatively calm to avoid spray drifting.
- Always follow label directions and obey all safety precautions.
For more information, please see the following sites: