GSOB Blitz

Join the 2025 FALL Goldspotted Oak Borer Blitz!

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Participants at field training in oak woodlands.
Field training with local community volunteers and land managers learning about GSOB.

Help us protect Southern California’s oak trees one hike at a time.


The goldspotted oak borer (GSOB) is a tiny beetle causing a big problem for Southern California’s oak trees. Its larvae tunnel beneath the bark and feed on the tissues that transport water and nutrients, slowly starving the tree from the inside out. After several years of repeated infestations, the damage becomes too much, and the tree dies. GSOB has already killed tens of thousands of mature oaks across the region.

But we can do something about it, and we need your help!
 

What’s a GSOB Blitz?

A GSOB Blitz is a community-powered effort to detect and map goldspotted oak borer infestations. With your help, we’ll survey oak trees across Southern California to identify where this pest is spreading, and how bad the damage is. These surveys help scientists and land managers decide where to take action to save our trees.

Even better? It’s a great way to learn, explore, and connect with nature while making a real impact. 

How it works:
  • Local survey events will take place across Southern California between designated dates.
  • Events are led by local agencies in collaboration with UC ANR and other partners.
  • Volunteers (like you!) will collect data in the field, after a brief training session.
  • You don’t need to be an expert; we’ll teach you everything you need to know! 
How to Participate

Step 1: Register Online.  

  • Register to a GSOB Blitz event! Links to online registration for each scheduled GSOB Blitz event are listed below. If you do not see an event planned in your area, subscribe to the GSOB Blitz listserv to let us know you are interested. We will keep you informed as new events are organized.
     
  • Following registration, you will receive more details via email. 
     
  • *Train-the-Trainer - Events designated as train-the-trainer are intended to equip those who will likely be educating others in their organizations or communities about GSOB and may potentially lead future GSOB Blitz groups. Instruction and field experience are similar to the general community volunteer GSOB Blitz but may include more technical terms and emphasis on various management and strategy options as well as resource supplies.
County:San Bernardino County 
Team Name:San Bernardino Mountains Land Trust GSOB Blitz 
Day/Date:Friday, October 24, 2025 
Time:9:00 AM - 1:00 PM 
Location:SBMLT Klamath Trailhead, 895 Needles Lane, Big Bear, CA 92314 
Minimum Age:Youth are welcome with parent/guardian supervision 
Contact/s: Karla Kellems, karlakellems@gmail.com, (760) 405-4311 
Liability:All Participants are required to sign a Participation Agreement / Waiver 
Registration:Online registration for this event hosted by the Sierra Club San Gorgonio 
   
County:San Bernardino County 
Team Name:San Bernardino Mountains Land Trust GSOB Blitz 
Day/Date:Sunday, October 26, 2025 
Time:12:00 PM - 4:00 PM 
Location:SBMLT Klamath Trailhead, 895 Needles Lane, Big Bear, CA 92314 
Minimum Age:Youth are welcome with parent/guardian supervision 
Contact/s: Karla Kellems, karlakellems@gmail.com, (760) 405-4311 
Liability:All Participants are required to sign a Participation Agreement / Waiver 
Registration:Online registration for this event hosted by the Sierra Club San Gorgonio 
   
County:Los Angeles County 
Team Name:Santa Monica Mountains GSOB Blitz 
Day/Date:Sunday, October 26, 2025 
Time:9:00 AM - 12:00 PM, noon 
Location:Malibu Creek State Park, 1925 Las Virgenes Rd, Calabasas, CA 91302 
Minimum Age:Youth are welcome with parent/guardian supervision 
Contact/s: Rachel Burnap,
rburnap@acwm.lacounty.gov
 
 Alyssa Morgan,
amorgan@rcdsmm.org
 
Registration:https://surveys.ucanr.edu/survey.cfm?surveynumber=47074 
   
County:Los Angeles County 
Team Name:Placerita Canyon GSOB Blitz 
Day/Date:Tuesday, October 28, 2025 
Time:9:00 AM - 12:00 PM, noon 
Location:Placerita Canyon Nature Center, 19152 Placerita Canyon Rd, Newhall, CA 91321 
Minimum Age:Youth are welcome with parent/guardian supervision 
Contact/s: Cristhian Mace,
cmace@parks.lacounty.gov 
 
Registration:https://surveys.ucanr.edu/survey.cfm?surveynumber=47101 
   
County:Los Angeles County 
Team Name:Santa Susana Mountain Area GSOB Blitz – Train-the-Trainer* 
Day/Date:Wednesday, October 29, 2025 
Time:9:00 AM - 12:00 PM, noon 
Location:East and Rice Canyon Trailhead, 23801 The Old Road, Newhall CA 91321 
Minimum Age:Adults only 
Contact/s: Rachel Burnap,
rburnap@acwm.lacounty.gov
 
 Alyssa Morgan,
amorgan@rcdsmm.org
 
Registration:https://surveys.ucanr.edu/survey.cfm?surveynumber=47076 
   
County:Riverside County 
Team Name: MCFSC Bug Busters! GSOB Blitz with the Santa Rosa Band of Cahuilla Indians 
Day/Date:Saturday, November 1, 2025 
Time:10:00 AM - 1:00 PM 
Location:Santa Rosa Tribal Administration Hall 65199 CA-74, Mountain Center, CA 92561 
Restrictions:8 years old and up. Minors must have Release Waiver signed by parent/guardian.
This Blitz is intended solely for members of the Santa Rosa Band of Cahuilla Indians, and is on their privately-held reservation land.
 
Contact/s: Callie Squires or Kim Fryer
951-659-6208; Email: gsob@mcfsc.org
 
Registration:https://surveys.ucanr.edu/survey.cfm?surveynumber=47098 
Flyer:Download local flyer 
   
County:Riverside County 
Team Name: VHOR Reconnaissance 
Day/Date:Wednesday, November 5, 2025 
Time:9:00 AM - 12:00 PM, noon 
Location:Valley Hi Oak Reserve, 47501 Twin Pines Rd, Banning, CA 92220 
Minimum Age:18 years old and up. 
Contact/s: Adrian Luis Poloni, CALFIRE
916-476-9883; Email: adrian.poloni@fire.ca.gov
 
 Kalee Koeslag, Riverside County Parks
Email: KKoeslag@rivco.org
 
Registration:https://surveys.ucanr.edu/survey.cfm?surveynumber=47113 
Flyer:Download local flyer 
   
County:Riverside County 
Team Name:MCFSC Bug Busters! GSOB Blitz - Idyllwild 
Day/Date:Saturday, November 8, 2025 
Time:10:00 AM - 1:00 PM 
Location:MSFSC Office 25380 Franklin Drive, Idyllwild, CA 92549. We will carpool to survey location(s). 
Restrictions:High school students only. Must be enrolled at Hamilton or Hemet High, or being homeschooled at a secondary school level. Minors must have Release Waiver signed by parent/guardian. 
Contact/s: Callie Squires or Kim Fryer
951-659-6208; Email: gsob@mcfsc.org
 
Registration:https://surveys.ucanr.edu/survey.cfm?surveynumber=47100 
Flyer:Download local flyer 

 

Step 2: Get Trained

  • Complete the Online GSOB Course (approximately 1 hour). Instructions for accessing the course, HERE.
  • Watch the GSOB Blitz Training Webinar recording held  May 27, 2025, 1:00–3:00 PM

Step 3: Join Your Survey Event

On the day of your local Blitz:

  • Meet your group at the designated time and place.
  • Receive your GSOB Blitz Bag with supplies and instructions.
  • Head out with your team to survey oak trees and collect data!

Ready to Make a Difference?

Let’s team up to stop GSOB and help keep Southern California’s oak woodlands healthy and thriving for wildlife, for people, and for future generations.
 

NOTE: SUBSCRIBE to the our primary GSOB listerv to receive news and information on goldspotted oak borer research, resources and upcoming events throughout the year.

Contact

Questions or more information about the GSOB Blitz can be directed to:
Jan Gonzales, Community Education Supervisor, UC Cooperative Extension
Email: jggonzales@ucanr.edu


Source URL: https://ucanr.edu/site/goldspotted-oak-borer/gsob-blitz