Pears and Fire Blight
Fire blight can affect all parts of a pear tree and, therefore, it can manifest itself in different ways. One of the most common and earliest occurring symptoms is blossom blight. When this occurs, the blossoms take on a gray and waterlogged appearance that eventually turns to black. The next very recognizable symptom is shoot blight, when new shoots turn black and wither, bending under their own weight into the shape of a candy cane. Sometimes, the blight will spread from the new shoots to the older wood, where it appears as sunken, oozing cankers. When fruit forms, fire blight in pears can result in fruits that are small, misshapen and covered in oozing lesions.
Treating Blight on Pear Trees
Fire blight overwinters in cankers in the wood. In the spring, the cankers ooze and the bacteria inside is carried to the blossoms by insects and moisture. Because of this, the best way to stop the cycle once it’s started is to remove and destroy all infected wood. Cut it away at least 8 inches (20 cm.) below the infection, and wipe your saw or shears in a 1:10 bleach to water solution after each cut. In the spring, immediately prune away any branches that show signs of shoot blight. To discourage the spread to blossoms, spray for small sucking insects, like aphids and leafhoppers. Insecticidal soaps can help early on with these pests.
