Fire blight is a bacterial disease destructive on many varieties of apples and pears but may also damage ornamental plants such as Bradford Pear. Infection normally occurs during the bloom period followed by infection on leaves, twigs and stems which turn brown and black giving it a scorched appearance, hence the name “Fire Blight." This year has been particularly bad due to ideal conditions for infection during the blooming period with many infected trees across the parish.
At this point in the season, control measures are limited, however, fire blight spread within trees can be reduced by applications of “fire blight spray” that include streptomycin or copper. Copper is the most readily available at local garden centers.
Sanitation may be beneficial as well by removing infected leaves, twig and stems and cutting back 3-4 inches beyond infection and totally removing and discarding from vicinity.
Ideal control measures begin with three applications of “fire blight spray” in late winter or early spring when Bradford Pears start blooming: 1st application at 5% blooms, 2nd at 25-30% blooms and 3rd at 50-60% blooms. This will help prevent the spread of the disease that may be present during bloom.
Rapidly growing, succulent twigs are most susceptible to fire blight bacteria. Excessive nitrogen fertilizer promotes this type growth so it is best to use a well balanced fertilizer with fairly low nitrogen for moderate growth if on a fertilizer program for Bradford Pears.
Contact your local parish office for further or related information at 318-728-3216.
The LSU AgCenter and the LSU College of Agriculture