DISEASE: Crown gall
HOST: Almond
Multiple galls on almond roots (left). Roots of healthy plant (right). Severe galling on young trees causes stunting.

Crown gall | Almond
DISEASE: Crown gall
HOST: Almond (Prunus dulcis)
PATHOGEN: Agrobacterium tumefaciens
PATHOGEN SYNONYM: Rhizobium sp.
SOURCE: M. Schroth
DISEASE: Drippy nut disease
HOST: Oak
Ooze from young twig inoculated with Brenneria quercina.

Drippy nut disease | Oak
DISEASE: Drippy nut disease
HOST: Oak (Quercus agrifolia)
PATHOGEN: Brenneria quercina
PATHOGEN SYNONYM: Erwinia quercina
SOURCE: M. Schroth
DISEASE: Drippy nut disease
HOST: Oak
Ooze from infected acorn. Copious ooze drips from infected acorns, leaving sticky spots on objects under tree canopy. Infections are associated with insect oviposit wounds.

Drippy nut disease | Oak
DISEASE: Drippy nut disease
HOST: Oak (Quercus agrifolia)
PATHOGEN: Brenneria quercina
PATHOGEN SYNONYM: Erwinia quercina
SOURCE: M. Schroth
DISEASE: European stone fruit yellows
HOST: Almond
The disease causes yellowing and rolling of leaves (right). Leaves become thick and rough in texture. Healthy leaves (left).

European stone fruit yellows | Almond
DISEASE: European stone fruit yellows
HOST: Almond (Prunus dulcis)
PATHOGEN: 'Candidatus Phytoplasma prunorum'
PATHOGEN SYNONYM: Phytoplasma Apple proliferation group
SOURCE: E. Seemueller
DISEASE: Foamy canker
HOST: Almond
White, macerated tissues near cambium region is characteristic of disease. Foam is usually associated with cankers. The disease is suspected to be bacterial but the causal agent has not been identified.

Foamy canker | Almond
DISEASE: Foamy canker
HOST: Almond (Prunus dulcis)
PATHOGEN: Causal agent unknown
SOURCE: B. Teviotdale