Olompali Galls and Other Natural Wonders

About this event

Olompali Galls and Other Natural Wonders Sunday, November 15, 2026 10 a.m. – 12:30 p.m. Leaders: Evan Weissman and Clint Kellner

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.

Cost: There is no charge for the event, but parking is $8. Pay by cash, check, or via smartphone with QR code at the parking lot. No parking fee is charged if you borrow a free State Park pass from your local public library.

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 Marin2026 Waiver

Practice clean trail etiquette: Pocket Guide - Every Step Counts and Cleanliness Tips for Hikers

From California Native Plant Society -- Marin Chapter Meetup