It kills the twigs, foliage, and fruit. The symptoms of fire blight are the same on pear as on apple, but are generally more severe on pear, even to the point of killing the tree. The wood of the infected twigs is black or dark brown and the bark is darker than normal. The edge of the infected area of bark is slightly sunken and very sharply defined. The most characteristic symptom is shown in the foliage and young fruit which are a black brown and remain firmly attached to the dead twig.
Infection occurs on the blossoms and spreads into the fruit spur and immediately adjacent branch.
Fortunately, this disease is only an occasional problem in Connecticut. Planting resistant cultivars such as Comice and Winter Nelis can essentially avoid this problem. When infections do occur, it is important to prune back to healthy wood during the dormant season, making sure to remove prunings from near the tree. The effects of this disease can be minimized by maintaining overall tree health and by avoiding practices, such as excessive fertilization, that can lead to excessive vigor in the tree. For more information, see the fact sheets on Disease Control for the Home Pear Orchard and on Fire Blight .