DISEASE: Marginal leaf blight
HOST: Lettuce
Marginal leaf blight first appears as slimy wilting of leaf margins. Small, reddish lesions may be seen on leaf blades. Infected tissues turn brown to black in time.

Marginal leaf blight | Lettuce
DISEASE: Marginal leaf blight
HOST: Lettuce (Lactuca sativa)
PATHOGEN: Pseudomonas marginalis
SOURCE: L. Fucikovsky
DISEASE: Shallow bark canker
HOST: Walnut
Diseased, discolored tissues revealed by removing external bark.

Shallow bark canker | Walnut
DISEASE: Shallow bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria nigrifluens
PATHOGEN SYNONYM: Erwinia nigrifluens
SOURCE: B. Teviotdale
DISEASE: Shallow bark canker
HOST: Walnut
Trunk with brown exudate shallow cankers.

Shallow bark canker | Walnut
DISEASE: Shallow bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria nigrifluens
PATHOGEN SYNONYM: Erwinia nigrifluens
SOURCE: B. Teviotdale
DISEASE: Shallow bark canker
HOST: Walnut
Multiple cankers with brown exudate. Cankers on trunk are shallow.

Shallow bark canker | Walnut
DISEASE: Shallow bark canker
HOST: Walnut (Juglans regia 'Hartley')
PATHOGEN: Brenneria nigrifluens
PATHOGEN SYNONYM: Erwinia nigrifluens
SOURCE: B. Teviotdale
DISEASE: Slime flux
HOST: Casuarina
Slime flux occurs on a number of tree species and is always associated with bacteria and yeast. However, the causal agent has not been identified.

Slime flux | Casuarina
DISEASE: Slime flux
HOST: Casuarina (Casuarina equisetifolia)
PATHOGEN: Causal agent unknown
SOURCE: W. Sinclair
DISEASE: Slime flux
HOST: Elm
Although bacteria are associated with slime fluxes of many trees, the causal agents have not been identified.

Slime flux | Elm
DISEASE: Slime flux
HOST: Elm (Ulmus pumila)
PATHOGEN: Causal agent unknown
SOURCE: W. Sinclair
DISEASE: Slime flux
HOST: Maple
The causal agent of slime flux has not been identified.

Slime flux | Maple
DISEASE: Slime flux
HOST: Maple (Acer saccharum)
PATHOGEN: Causal agent unknown
SOURCE: W. Sinclair