DISEASE: Crown gall
HOST: Aspen
Aspen with large, encrusted gall.

Crown gall | Aspen
DISEASE: Crown gall
HOST: Aspen (Populus sp.)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: S. Thomson
DISEASE: Dogwood stunt
HOST: Dogwood
Diseased plant with small leaves (left).

Dogwood stunt | Dogwood
DISEASE: Dogwood stunt
HOST: Dogwood (Cornus sp.)
PATHOGEN: 'Candidatus Phytoplasma asteris'
PATHOGEN SYNONYM: Phytoplasma Aster yellows group
SOURCE: W. Sinclair
DISEASE: Fire blight
HOST: Pear
Blossom blight is first seen as water-soaked spots that rapidly turn brown to black as the disease becomes systemic and progresses down the shoot.

Fire blight | Pear
DISEASE: Fire blight
HOST: Pear (Pyrus communis)
PATHOGEN: Erwinia amylovora
SOURCE: S. Thomson