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: 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
DISEASE: Fasciation (Shoot proliferation)
HOST: Heron's bill (Stork's bill)
Heron's bill with multiple shoots.

Fasciation (Shoot proliferation) | Heron's bill (Stork's bill)
DISEASE: Fasciation (Shoot proliferation)
HOST: Heron's bill (Stork's bill) (Erodium × variabile)
PATHOGEN: Rhodococcus fascians
SOURCE: M. Putnam
DISEASE: Gumming disease
HOST: Sugarcane
Symptoms include brownish red streaks on leaves with apical chlorosis. Streaks become necrotic with time. Plants are stunted with reddening of vascular bundles.

Gumming disease | Sugarcane
DISEASE: Gumming disease
HOST: Sugarcane (Saccharum officinarum)
PATHOGEN: Xanthomonas axonopodis pv. vasculorum
PATHOGEN SYNONYM: Xanthomonas campestris pv. vasculorum
SOURCE: APS