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: 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
DISEASE: Slime flux
HOST: Willow
Foam at site of infection. Slime fluxes are common but the causal agent has not been identified.

Slime flux | Willow
DISEASE: Slime flux
HOST: Willow (Salix sp.)
PATHOGEN: Causal agent unknown
SOURCE: S. Thomson
DISEASE: Witches'-broom
HOST: Alfalfa
Alfalfa plant (center) exhibiting stunting and proliferation of stems. Other symptoms are small, rounded, chlorotic, often puckered leaves and a yellowish cast.

Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson
DISEASE: Witches'-broom
HOST: Alfalfa
Young plant (left) with small, numerous stems (witches'-broom). Healthy stems (right).

Witches'-broom | Alfalfa
DISEASE: Witches'-broom
HOST: Alfalfa (Medicago sativa)
PATHOGEN: 'Candidatus Phytoplasma trifolii'
PATHOGEN SYNONYM: Phytoplasma Clover proliferation group
SOURCE: S. Thomson