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Caterpillar Defoliation of White Birch: Systemic Soil Treatment

Southern Ontario: 18 large white birches infested with caterpillars (no tents), stripping leaves. Heard of spring pour-on insecticide; asking if too late.

Advice

Pour-on works best spring-applied. Check garden center for current options. Natural predators often control outbreaks. Trees often releaf after caterpillar cycle completes.

Action

Consult local nursery for timing. Monitor—natural cycles may resolve it. Systemic soil treatments available for season-long protection.

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