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Arborvitae Top Dieback After Bagworms: Assessing Live Tissue and Recovery

A 12-ft arborvitae with dead top 4–5 ft after bagworm attack last summer may have secondary issues. Bagworms rarely kill entire leaders; check for live cambium before pruning.

Diagnosis

Scratch bark on dead-looking top: green underneath = alive; brown = dead.
If alive: it will regrow; fertilize lightly, water during drought.
If dead: prune back to live wood (green cambium).

Additional Checks

Inspect for remaining bagworm cases; remove manually.
Look for spider mites (common on stressed arborvitae).
Ensure no girdling roots or trunk injury at base.

Care

Water deeply weekly in dry weather.
Apply slow-release evergreen fertilizer in spring.
Monitor new growth for pests.

Arborvitae often recover from bagworm defoliation if secondary stressors are managed.

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