DISEASE: Ash yellows
HOST: Ash
Ash sapling with basal sprouts and chlorotic leaves.

Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus pennsylvanica)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
Witches'-broom at base of declining tree.

Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus velutina)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
Forest of declining trees, some chlorotic and others with dieback.

Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus americana)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Ash yellows
HOST: Ash
White ash with deliquescent branching.

Ash yellows | Ash
DISEASE: Ash yellows
HOST: Ash (Fraxinus americana)
PATHOGEN: 'Candidatus Phytoplasma fraxini'
PATHOGEN SYNONYM: Phytoplasma Ash yellows group
SOURCE: W. Sinclair
DISEASE: Bacterial blight
HOST: Hazelnut
Diseased young tree with discoloration of the cambium. Dieback of young twigs and branches is characteristic. Other typical symptoms are bud and twig necrosis and small, angular or round, water-soaked leaf spots.

Bacterial blight | Hazelnut
DISEASE: Bacterial blight
HOST: Hazelnut (Corylus americana)
PATHOGEN: Xanthomonas arboricola pv. corylina
SOURCE: J. Pscheidt
DISEASE: Bacterial wilt
HOST: Bean
Bean leaf with white pustules following inoculation. Stem inoculation causes veinal yellowing and necrosis of leaves. Infected seed may be purple or yellow.

Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: L. Claflin
DISEASE: Bacterial wilt
HOST: Bean
Leaves with interveinal chlorosis and necrosis. Healthy (right).

Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: APS
DISEASE: Bacterial wilt
HOST: Bean
Bean seeds infected with orange (upper right), violet (upper left), and yellow (lower left) variants of Curtobacterium flaccumfaciens. White seed in the lower right is healthy.

Bacterial wilt | Bean
DISEASE: Bacterial wilt
HOST: Bean (Phaseolus vulgaris)
PATHOGEN: Curtobacterium flaccumfaciens pv. flaccumfaciens
SOURCE: APS