Trail Closures May 4th to May 7th 2021

Please notice that from Tuesday May 4th to Friday May 7th some sections of the trails in the Preserve will be closed. Volunteers and park rangers will be on location from 6 AM to 1 PM while pesticide application takes place.

Several hundred coast live oak trees in the Preserve and all over San Diego County are infested with Gold spotted oak borer (GSOB). The insect larvae feed under the bark and destroy the cells that transport water and nutrients inside the tree. As adults, they bore a small D-shaped exit hole in the bark to fly and lay eggs on the bark of other oak trees. The GSOB has spread on firewood, so infested wood must not be moved or used as firewood until a tree has been dead for two years. For the past 3 years, the Friends have conducted field surveys recording the location of infested trees in the Preserve, and have sponsored management actions with the goal of slowing but not eliminating the infestations and the tree mortality.

Here is a message from Ranger Gina Washington:

Good Morning,

I want to make you aware of this week’s trail closures. We are treating the oak trees for Gold Spotted Oak Borer, a beetle that kills California Coast Live Oaks. We have been successful in slowing the spread of this destructive pest through the targeted spraying of a specific pesticide over the last several years, but we must be vigilant to maintain the oak we have. Therefore, portions of trails will be closed this week for the application.

Tuesday, May 4 the Staging Area off Black Mountain Rd and all South Side trails between Black Mountain Road and Peñasquitos Creek Crossing – Closed 6:00 am to 1:00 pm

Wednesday, May 5 All South Side Trail between Ranch House Crossing and the Waterfall - Closed 6:00 am to 1:00 pm

Thursday, May 6 All North Side Trails between the Ball Fields and the Waterfall - Closed 6:00 am to 1:00 pm

Friday, May 7 Trans County Trail east of Black Mountain Road to I-15 - Closed 6:00 am to 1:00 pm

Gina Washington

Senior Park Ranger

City of San Diego