Olompali Galls and Other Natural Wonders

Leaders: Evan Weissman and Clint Kellner

Please sign up for this field trip on Meetup       Limit 25 people

Club Gall Wasp

Join our search for some of the most mysterious and seldom-noticed natural wonders: Galls! Plant galls are growths induced by insects or other organisms, and they come in a wide variety of shapes and colors which give clues to the organism (often a tiny wasp) which caused the growth. Leaders Clint Kellner and Evan Weissman will share their knowledge, fascination, and curiosity about the galls and other lifeforms that we find along the way.

We’ll walk at a fairly slow pace, about 1 mile round trip, on gravel and dirt trails, portions of the trail with a gentle slope. We may be stepping into tall grass for good looks at the galls. There are several picnic tables to rest along the partially-shaded route.

Directions: Meet at 10am in the Olompali State Historic Park parking lot. The entrance is at the end of Redwood Boulevard. From either north or south on Highway 101, take the Atherton/San Marin exit and proceed west and then turn right (north) onto Redwood Boulevard which is the first street west of the freeway.

State Park Parking Fee:   $8. Pay by cash, check, or via smartphone with QR code. For Free Parking borrow a State Park Pass from your local library.

Questions: Email Clint Kellner

Text for day-of-trip questions or issues: (415) 895-8591

Bring: Dress in layers, long pants, and walking shoes. Bring sunscreen, snacks, and plenty of water.

Heavy Rain cancels. Check Meetup for notification.

Waiver:  If you have not done so already, please sign the CNPS Marin 2026 Waiver

Practice clean trail etiquette.  Pocket Guide – Every Step Counts and  Cleanliness Tips for Hikers