The Town of Wake Forest is urging area landowners with apple and pear trees on their property to be on the lookout for signs of fire blight.
According to the N.C. Cooperative Extension Service, fire blight causes a distinct blackening of leaves and young shoots, making it look like trees have been burned with a blowtorch.
Fire blight usually begins as a disease on blossoms and is caused by bacteria spread mainly by bees as they visit the flowers in the spring. It proliferates during periods of rainy, warm weather.
Signs and symptoms of blossom infections include blackened, shriveled flowers and orange ooze near blossoms. As the disease progresses, it moves down from the blossom into the tree’s shoots and eventually the tree’s branches.
Infections may also be evident as oval-shaped dead areas on a tree’s branches or trunk. In early spring, when weather conditions are favorable, orange ooze may be visible around the edge of the dead area. The sticky ooze is the bacterium, which will then be spread by splashing rain and insects. In extreme cases, the disease will colonize the entire tree, killing it.
Although fire blight is most often seen on apple and pear trees (including Asian pears), the disease can also affect cotoneaster and Indian hawthorn plants. It is especially common on Bradford pears, which are widely planted in the landscape.
If you have a plant with fire blight, the best option is to prune out the infection while the plant is dormant in the winter. Pruning cuts should be made four-to-six inches below the discolored area of the branch. When infections are noticed during the spring and summer, prune 12” below the discolored portion. In conjunction with pruning, streptomycin sprays during bloom may also be helpful.
If you are considering planting apple or pear trees, choose varieties that are resistant to fire blight. A list of varieties and their resistance rating are provided online at http://go.ncsu.edu/mky3yi.
For more information about fire blight, contact Urban Forester Evan Keto at 919-435-9565 or eketo@wakeforestnc.gov.
