Crown gall—Agrobacterium tumefaciens
Trees infected with crown gall have rough, warty tumors on large roots near the crown. Galls first appear
as smooth swellings and develop into large tumors with a rough, warty, or cracked appearance. On blackberries,
raspberries, and grapes, galls may also form on stems.
Life cycle
Solutions
You can greatly reduce problems with crown gall by obtaining planting material from a reputable nursery.
Examine bare-root trees and vines before purchase. Avoid injury or pruning wounds that will come into
contact with soil. Larger trees and vines can usually tolerate the development of crown galls. | 
Warty
tumors on large roots near crown area
Galls
on roots
|
