DISEASE: Deep bark canker
HOST: Walnut
Pits in the wood and black streaks in inner bark are key diagnostic symptoms.
![](/sites/default/files/plant_disease/images/0968.jpg)
Deep bark canker | Walnut
DISEASE: Deep bark canker
HOST: Walnut (Juglans regia)
PATHOGEN: Brenneria rubrifaciens
PATHOGEN SYNONYM: Erwinia rubrifaciens
SOURCE: N. Schaad, M. Schroth
DISEASE: Pear decline
HOST: Pear
'Bartlett' pears were grafted onto tolerant rootstock. All trees are infected. Note yellowish, diseased branches.
![](/sites/default/files/plant_disease/images/0697.jpg)
Pear decline | Pear
DISEASE: Pear decline
HOST: Pear (Pyrus communis 'Bartlett')
PATHOGEN: 'Candidatus Phytoplasma pyri'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: C. Smart