Sudden Oak Death
Phytophthora ramorum
severe risk
plant_disease
Overview
Devastating water mold disease killing millions of oaks and tanoaks in California and Oregon. Major threat to European forests.
Bleeding cankers on oak bark (dark oozing sap). Sudden wilting and browning of foliage. Dead foliage remains attached.
Prevention Strategies
- •Quarantine nursery plants from infected regions
- •Do not move soil, plant material from infected areas
- •Eradicate bay laurel near oaks in high-risk areas
Control Methods
- •Phosphonate fungicide injections for individual high-value trees
- •Remove infected trees and woody debris
- •No cure - prevention and containment only
Interesting Facts
- •Bay laurel hosts and spreads disease without dying - perfect asymptomatic reservoir
- •Has killed over a million tanoak trees in coastal California
- •First detected in mid-1990s, cause identified 2000
- •International nursery trade has spread pathogen to many countries from California