Infected apple tree with brown (necrotic) shoots. Infections can lead to branch dieback and death of susceptible trees. Infection of the new shoots usually occurs in the spring. Photo courtesy of University of Minnesota Plant Disease Clinic.
Infected shoots appear brown or black (as if scorched by fire) and curled. The characteristic curling of a shoot is referred to as a shepherd's crook. Photo courtesy of University of Minnesota Plant Disease Clinic.
Disease cycle of the fireblight bacterium. Bacteria are spread from infected plants to healthy plants via insects (bees).
Photo courtesy of American Phytopathological Society.
Disease cycle of fireblight. In the spring, bacteria multiply and are rain splashed to susceptible tissue.
Photo courtesy of American Phytopathological Society.
Next |
Back to Diseases of Deciduous Trees
(C) Regents of the University of
Minnesota. All rights reserved. |