Sudden Oak Death (SOD) has become one of the most serious threats to California’s forests and residential landscapes. This invasive disease—caused by the water mold Phytophthora ramorum—has killed hundreds of thousands of oaks and tanoaks across the state and continues to spread.

Understanding the Threat

SOD infects oaks and tanoaks through bark and leaves, causing bleeding cankers, dieback, and ultimately tree death. Once established in an area, it can move quickly through wind-driven rain, infected soil, and plant material. Early detection and proactive treatment are essential to saving valuable trees.

Science-Based Treatment

Our Northern California crews stay current with the latest research from the University of California, Berkeley’s Forest and Plant Mycology and Pathology Department. Following their recommendations, we treat susceptible oaks with Agrifos®, a proven phosphonate fungicide. When applied properly, Agrifos can help boost the tree’s natural defenses and slow the progression of SOD.

Our Approach

• Monitoring & Diagnosis: We inspect your oaks for early signs of infection and sample as needed.
• Targeted Agrifos Application: Treatments are applied at the correct time of year and dosage for maximum effectiveness.
• Integrated Care: We pair treatments with best practices such as sanitation of equipment and proper disposal of infected debris to limit further spread.

Take Action Now



If you have oaks on your property, now is the time to act. Preventative care can mean the difference between saving a healthy tree and losing it to Sudden Oak Death.

Contact our team to schedule an evaluation. Together, we can help protect Northern California’s iconic oaks for future generations.

For more information on Sudden Oak Death research and treatment guidelines, visit UC Berkeley’s Forest and Plant Mycology and Pathology resources.