Pear trees (Pyrus communis) are hardy, deciduous trees native to Asia and Europe. They typically grow very quickly, bearing fruit three to five years after planting. Pear trees have glossy green leaves and are easy to grow, but they can be susceptible to diseases.
Fire blight (Erwinia amylovora) is a bacterial disease that causes severe symptoms. Blighted pear blossoms are brown, shriveled and wilted, while blighted pear shoots turn black.
Fabraea Leaf Spot
Fabraea leaf spot (Fabraea maculate) causes affected pear trees to defoliate early, resulting in smaller fruit and fewer fruit buds. It can be identified by small, circular purplish-black spots on leaves, fruits and shoots.
Pear scab, often called black spot, is caused by a fungus (Venturia pirina). This fungal disease causes round, brown lesions to form on the pear tree’s petioles and leaves.
Stony pit is a viral disease common to the Bosc pear variety. Stony pit causes pear pit cells to fuse into a stony, cone-shaped mass.
Several management practices can reduce the risk of pear tree diseases, including controlling the insect population. Pear trees should not be overfertilized or watered with overhead sprinklers.