Bacterial Leaf Scorch

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What is Bacterial Leaf Scorch? How does it hurt my tree?
Bacterial Leaf Scorch (BLS) is caused by the bacterium Xylella fastidiosa. It’s a systemic disease which invades the xylem (tissues that conduct water and nutrients) and clogs the tissue, thus disrupting the transportation of water. BLS affects many woody and herbaceous plants and is known to be spread primarily by spittlebug (Cercopidae) and leafhopper (Cicadellidae) insect families. Xylella fastidiosa also causes Pierce’s Disease of grapevines and Phony Peach Disease.
What are the symptoms?
The leaves of the tree will start to brown prematurely in midsummer. By late summer and fall the leaf margins will be entirely brown. Sometimes the dead brown tissue is separated from the healthy green tissue by a thin yellow border. As more leaves continue to turn brown prematurely, the tree will die from lack of energy production due to the absence of chlorophyll (and consequently, photosynthesis).
With what is it sometimes confused?
BLS is sometimes confused with Oak Wilt, Dutch Elm Disease and traditional leaf scorch (caused by cultural practices such as over-fertilization).
What species are affected?
American Sycamore, mulberry, grape, American elm, sweetgum, boxelder, dogwood, red maple and sugar maple. Oaks species affected are bur, live, pin, scarlet, shingle, southern red, water and willow.
How can BLS be treated?
There is no cure for BLS once the bacteria is present. Good management practices can delay onset and extend longevity of the tree. Proper irrigation and mulching of the tree is a good start. Analyze soil before applying any fertilizer. Monitor and treat BLS infected trees annually to prevent worsening.