Symptoms and Types of
Fire Blight |
Click here for an enlarged picture. |
Click here for an enlarged picture. |
 Shoot
Blight
occurs when vegetative shoot tips are invaded. The tip of the shoot
will wilt and curve downward like a sheperds crook, and then the shoot
(and possibly the entire branch) will die. |
Click here for an enlarged picture. |
Click here for an enlarged picture. |
Blossom
Blight
occurs when bacteria invade open flowers. The flower base and petiole
will darken and ooze tiny droplets. Then the petiole will wilt.
Canker
Blight
occurs when bacteria near last year's cankers renew their activity.
First, the bark near an old canker will become infected. Then nearby
vegetative shoots will begin to wilt, and their tips will look yellow
or orange.
Trauma
Blight
occurs when injuries caused by wind, hail, frost, or late pruning
weaken the tissue and allow disease in. The infections can look
like shoot or canker blight.
Rootstock
Blight occurs when bacteria from other infections on the tree
move into the rootstock. A canker will form in the lower trunk that
will girdle and kill the tree. Cankers will be visible on the scion
trunk only, and infected trees may produce red leaves early in the
fall.
