Resource Database

Fire blight is caused by the bacterium Erwinia amylovora. Fire blight can be a persistent disease problem for the Callery pear (Pyrus calleryana ‘bradford’). This disease can also affect some varieties of bearing pear, apple, flowering crabapple, pyracantha, blackberry, and quince.  Rose, cotoneaster and hawthorn are also attacked but to a lesser extent. Leaves wilt and rapidly turn dark brown. Affected leaves tend to cling to the branches rather than fall to the ground. Twig tips appear as if they were scorched by fire or damaged by frost and may be randomly distributed. Twig tips may also develop a “shepherd’s crook,” which is useful in disease diagnosis.

• Ornamentals
  • Trees