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: Bacterial leaf spot
HOST: Hydrangea (Oak-leaf)
Leaf with individual brown necrotic lesions and coalesced lesions that formed large necrotic areas. The disease is caused by an unclassified xanthomonad.

Bacterial leaf spot | Hydrangea (Oak-leaf)
DISEASE: Bacterial leaf spot
HOST: Hydrangea (Oak-leaf) (Hydrangea quercifolia)
PATHOGEN: Xanthomonas campestris
SOURCE: W. Uddin, W. Sinclair
DISEASE: Bacterial wilt
HOST: Squash
Field with severe symptoms of wilt. Foliage often is chlorotic and leaf margins may be chlorotic and necrotic before plant death. Bacterial ooze may be seen streaming from the xylem when infected stems are cut.

Bacterial wilt | Squash
DISEASE: Bacterial wilt
HOST: Squash (Cucurbita maxima)
PATHOGEN: Erwinia tracheiphila
SOURCE: B. Jacobsen, M. Shurtleff