UPDATE 6/13/24:
Following a comprehensive assessment following the tree’s diagnosis of Oak Root Fungus (Armillaria mellea) it has been determined that the American Elm poses no imminent danger. As a result, the barricades have been removed around the tree.
Original Post
For public safety, a portion of the Northeast quadrant of Sonoma Plaza Park near the Bear Flag Statue is temporarily closed.
Important Safety Information: A large American Elm in the park has been diagnosed with Oak Root Fungus (Armillaria mellea), a serious condition that compromises the tree’s stability. The tree exhibits extensive fungal growth around its base, indicating a highly infected root system. This makes the tree unstable and at risk of collapsing.
Closure Details:
- Affected Area: The immediate vicinity around the infected American Elm
- Reason: Risk of whole tree failure due to compromised root system
- Safety First: This area is off-limits to all visitors
About Oak Root Fungus:
- Affects tree roots, moving up to the root collar and trunk
- Causes root rot and can lead to tree collapse
- Learn more about the disease on the University of California Agriculture & Natural Resources website.
Next Steps: The infected tree will undergo further evaluation to determine if it can be saved. While the disease is not expected to spread to other trees, the City will develop a comprehensive management plan to monitor and protect other park trees.
We appreciate your understanding and cooperation as we work to maintain a safe and beautiful park for everyone. Thank you for your patience and cooperation.