Acute oak decline

Caused by 2 bacteria: Gibbsiella quercinecans and Brenneria goodwinii

Oaks that are less than 50 years old can suddenly dry out and die within 2–3 years. The disease is caused by bacteria that have only recently been discovered by scientists: Gibbsiella quercinecans and Brenneria goodwinii. In the spring and fall, a dark, sticky liquid runs down the trunk of the bacteria-infected tree. Dark, wet spots are visible if the bark is ripped off in these areas. Larvae of the two‐spotted oak buprestid beetle (Agrilus biguttatus) are almost always found under the infected bark. Dry weather and beetle larvae damage may also contribute to the death of infected trees. The disease is still being researched.