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 leaf spot
HOST: Cherry laurel
Leaves with typical necrotic spots.

Bacterial leaf spot | Cherry laurel
DISEASE: Bacterial leaf spot
HOST: Cherry laurel (Prunus laurocerasus)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: A. Hagen, W. Sinclair
DISEASE: Bacterial spot
HOST: Almond
Leaves exhibiting different stages of disease. Spots begin as water-soaked lesions, mostly at leaf tips and margins, and later turn brown.

Bacterial spot | Almond
DISEASE: Bacterial spot
HOST: Almond (Prunus dulcis)
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: J. Young
DISEASE: Bacterial spot
HOST: Apricot
Fruit with black scabs and cracks, and leaves with brown lesions, some coalescing to form large necrotic areas.

Bacterial spot | Apricot
DISEASE: Bacterial spot
HOST: Apricot (Prunus armeniaca 'Moorpark')
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: J. Young
DISEASE: Bacterial spot
HOST: Nectarine
Nectarine with necrotic spots on leaves and dark necrotic spots on fruit.

Bacterial spot | Nectarine
DISEASE: Bacterial spot
HOST: Nectarine (Prunus persica var. nucipersica 'Redgold')
PATHOGEN: Xanthomonas arboricola pv. pruni
PATHOGEN SYNONYM: Xanthomonas campestris pv. pruni
SOURCE: J. Young