A disease of willow trees caused by obstruction of xylem vessels by the bacterium Brenneria salicis, producing dieback in the crown and stains in the wood, especially in the cricket-bat willow, Salix alba var. caerulea.
Origin
1920s.
Definition of watermark disease in US English:
watermark disease
noun
A disease of willow trees caused by obstruction of xylem vessels by the bacterium Brenneria salicis, producing dieback in the crown and stains in the wood, especially in the cricket-bat willow, Salix alba var. caerulea.