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red-cage fungus in California

MODERATE

Fungus

Active now in California

red-cage fungus is currently active in California. Watch your susceptible trees closely and act early.

About red-cage fungus

red-cage fungus observed in the wild. Research-grade iNaturalist observation.

Symptoms to watch for

Treatment options

Fungicide Application

Chemical TreatmentEffectiveness: HIGH

Apply systemic or contact fungicide at the first sign of infection. Repeat applications may be needed during wet weather. Follow label rates and timing.

Sanitation and Pruning

Cultural PracticeEffectiveness: MODERATE

Remove and destroy all infected leaves, branches, and fallen debris. Improve air circulation by thinning dense canopy growth. Sterilize pruning tools.

Soil and Moisture Management

Cultural PracticeEffectiveness: MODERATE

Ensure proper drainage, avoid overwatering, and apply mulch to reduce soil splash. Many fungal pathogens thrive in persistently wet conditions.

Recommended Products & Tools

Helpful supplies for managing red-cage fungus. Always read and follow label directions, and confirm a diagnosis before treating.

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Need help with red-cage fungus in California?

Connect with ISA Certified Arborists serving California:

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Frequently asked questions

Is red-cage fungus in California?

red-cage fungus is currently active in California. Watch your susceptible trees closely and act early. It was first recorded here on March 27, 2026.

What does red-cage fungus look like?

How do I treat red-cage fungus?

Options include: Fungicide Application, Sanitation and Pruning, Soil and Moisture Management. Confirm the diagnosis before treating, and consider a certified arborist for high-value trees.