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Bacterial Leaf Scorch of Oak and Other Hardwoods

BACTERIAL LEAF SCORCH (BLS) of hardwood trees, shrubs, and herbaceous plants, is caused by the bacterium, Xylella fastidiosa, carried by small insects such as leaf hoppers and sharpshooters. BLS has been very damaging to red oaks in Delaware and the Mid-Atlantic states for over 15 years. Northern red oak and pin oaks under environmental stress are most susceptible. Symptoms include marginal discoloration or scorch of leaves in late summer or early fall, often with a yellow or dark band on the inside edge of the discolored area. Symptoms are similar to those caused by drought or root issues that interfere with flow of water and nutrients. Plants may not develop symptoms for a year or two after infection, but then thinning of branches occurs and trees die within 5 to 8 years.  Infection is confirmed with a lab test for a fee; please arrange to have samples tested by contacting the UDBLS Red Oak 2016 Plant Diagnostic Clinic. There is a $20 fee for BLS testing. To manage, maintain good tree vigor, and remove infected trees. A UD fact sheet has more info: http://extension.udel.edu/factsheets/bacterial-leaf-scorch/
NFG 9/1/2017

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About cmanneri

Christy is a graduate of the Biden School of Public Policy and Administration at the University of Delaware with a master's in Public Administration. She is the chief operating officer of a local non-profit, 3B Brae’s Brown Bags and a Communications Specialist for the University of Delaware. Her research interests include issues of social justice, such as nutritional insecurity, community re-entry, and domestic violence. She also volunteers with her local school district and has a deep passion for education policy, as she believes many social injustices stem from inequitable opportunities in education.