TreeIssues

Anise Swallowtail in California

MODERATE

Insect

Active now in California

Anise Swallowtail is currently active in California. Watch your susceptible trees closely and act early.

About Anise Swallowtail

Chunky 5th-instar Anise swallowtail caterpillar found on some wild fennel at the side of the freeway overpass. It's a common sight here, but what isn't is the pattern. I mean, just look how uneven those bands are!

Symptoms to watch for

Treatment options

Targeted Insecticide Application

Chemical TreatmentEffectiveness: HIGH

Apply appropriate insecticide following label directions. Timing is critical — treat during the vulnerable larval or adult emergence stage for maximum effectiveness.

Biological Control Agents

Biological ControlEffectiveness: MODERATE

Introduce or encourage natural predators and parasitoids. Options include releasing predatory beetles, parasitic wasps, or applying Bt (Bacillus thuringiensis) for caterpillar pests.

Infested Material Removal

Mechanical RemovalEffectiveness: MODERATE

Prune and destroy infested branches and plant material. Remove fallen debris that may harbor eggs or larvae. Dispose of material away from healthy trees.

Recommended Products & Tools

Helpful supplies for managing Anise Swallowtail. Always read and follow label directions, and confirm a diagnosis before treating.

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Need help with Anise Swallowtail in California?

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Frequently asked questions

Is Anise Swallowtail in California?

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

What does Anise Swallowtail look like?

How do I treat Anise Swallowtail?

Options include: Targeted Insecticide Application, Biological Control Agents, Infested Material Removal. Confirm the diagnosis before treating, and consider a certified arborist for high-value trees.