DISEASE: Bacterial blight (Black leaf blight)
HOST: Canna
Canna with blighted shoots and leaves.

Bacterial blight (Black leaf blight) | Canna
DISEASE: Bacterial blight (Black leaf blight)
HOST: Canna (Canna indica)
PATHOGEN: Xanthomonas campestris pv. cannae
SOURCE: D. Shoenweiss, M. Shurtleff
DISEASE: Bacterial blight (Black leaf blight)
HOST: Canna
Canna with yellowing and blackened tissues.

Bacterial blight (Black leaf blight) | Canna
DISEASE: Bacterial blight (Black leaf blight)
HOST: Canna (Canna sp.)
PATHOGEN: Xanthomonas campestris pv. cannae
SOURCE: A. Alvarez
DISEASE: Bacterial leaf spot
HOST: Elm
Leaf with small, dark brown lesions and necrosis along veins.

Bacterial leaf spot | Elm
DISEASE: Bacterial leaf spot
HOST: Elm (Ulmus americana)
PATHOGEN: Pseudomonas syringae pv. ulmi
SOURCE: W. Sinclair
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Mandarin orange)
The bacterium invades the tree slowly, leading to yellowing of the entire canopy. Pale yellow, blotchy mottled leaves are reduced in size.

Citrus greening (Huanglongbing) | Citrus (Mandarin orange)
DISEASE: Citrus greening (Huanglongbing)
HOST: Citrus (Mandarin orange) (Citrus reticulata)
PATHOGEN: 'Candidatus Liberibacter asiaticus'
PATHOGEN SYNONYM: Candidatus Liberobacter asiaticus
SOURCE: S. M. Garnsey
DISEASE: Elm leaf scorch
HOST: Elm
Diseased tree with scorch at leaf margins.

Elm leaf scorch | Elm
DISEASE: Elm leaf scorch
HOST: Elm (Ulmus americana)
PATHOGEN: Xylella fastidiosa
SOURCE: J. Sherald, M. Shurtleff
DISEASE: Elm leaf scorch
HOST: Elm
Severely diseased tree with dieback and scorched leaves.

Elm leaf scorch | Elm
DISEASE: Elm leaf scorch
HOST: Elm (Ulmus americana)
PATHOGEN: Xylella fastidiosa
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Symptoms of elm yellows occasionally appear on one branch before others, but more often they involve the entire crown.

Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Diseased twig (right) with epinasty, chlorosis, and yellowing of leaves. Sometimes both yellow and green leaves occur on same branch. Healthy branch (left).

Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair
DISEASE: Elm yellows
HOST: Elm
Branches with butterscotch discoloration (center) and necrotic flecks in phloem and vascular cambium (right). Healthy branch (left). Sudden wilt and browning is common with small trees.

Elm yellows | Elm
DISEASE: Elm yellows
HOST: Elm (Ulmus americana)
PATHOGEN: 'Candidatus Phytoplasma ulmi'
PATHOGEN SYNONYM: Phytoplasma Elm yellows group
SOURCE: W. Sinclair