Section of Sonoma Plaza Park Closed Due to Tree Hazard

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.