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 canker (Leaf spot)
HOST: Mume (Japanese apricot)
Leaves with spots surrounded by yellow halos.

Bacterial canker (Leaf spot) | Mume (Japanese apricot)
DISEASE: Bacterial canker (Leaf spot)
HOST: Mume (Japanese apricot) (Prunus mume)
PATHOGEN: Pseudomonas syringae pv. morsprunorum
SOURCE: M. Goto
DISEASE: Bacterial canker
HOST: Cherry
Cherry with necrotic internal tissues and external symptoms of ooze (gummosis) caused by systemic infection.

Bacterial canker | Cherry
DISEASE: Bacterial canker
HOST: Cherry (Prunus avium)
PATHOGEN: Pseudomonas syringae pv. morsprunorum
SOURCE: D. Funk, A. Alvarez
DISEASE: Bacterial canker
HOST: Cherry
Systemic infection of petioles and leaves.

Bacterial canker | Cherry
DISEASE: Bacterial canker
HOST: Cherry (Prunus avium)
PATHOGEN: Pseudomonas syringae pv. morsprunorum
SOURCE: D. Funk, A. Alvarez
DISEASE: Bacterial wilt
HOST: Alfalfa
Longitudinal section of defined brown gum pockets on inner surface of root bark.

Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: S. Thomson
DISEASE: Bacterial wilt
HOST: Alfalfa
Infected plant (left) with typical symptoms of stunting and chlorosis. Other characteristic symptoms are spindly stems and small distorted leaflets. Healthy plant (right).

Bacterial wilt | Alfalfa
DISEASE: Bacterial wilt
HOST: Alfalfa (Medicago sativa)
PATHOGEN: Clavibacter michiganensis subsp. insidiosus
SOURCE: S. Thomson