Seasonal guide

The SOD year

Prevention is entirely about timing. Current month outlined; fall treatment window shaded.

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

California (UC IPM / COMTF guidance)

Sep–Nov (fall): THE season. Phosphonate (Agri-Fos) preventive treatment window opens Oct–Dec — schedule a licensed applicator. Remove bay laurels within 15–30 m of valued oaks before the rains. Finish all pruning by end of November. [COMTF Treatments]
Dec–Feb (winter): Rainy season = infection season. No pruning. Clean tools, boots, and tires after wet woodland work. [UC IPM]
Mar–May (spring): Symptoms show on bay leaves — inspect now. Second treatment window (first-year protection) after new leaves emerge. SOD Blitz surveys run — free lab testing. [SOD Blitz]
Jun–Aug (summer): Dry-season window for bay removal and safe pruning. Get applicator quotes for fall. Watch oaks for bleeding cankers. [COMTF Homeowner Guide]

Oregon (ODA/ODF program — different rules)

Oregon runs an eradication program centered on the Curry County quarantine area. Year-round: report suspected symptoms to ODF or the Oregon Invasive Species hotline (1-866-INVADER) rather than treating on your own, and never move host plants, soil, or firewood out of the quarantine area. [Oregon ODA SOD Program]