Hikers in Russian Ridge Open Space Preserve / photo by Lanette Otvos

My Gall Friday

Friday, March 20, 2026
9:00 am - 12:00 pm
Bear Creek Redwoods Preserve
Approximate Total Miles
4

Witches’ brooms, oak apples, redwood burls, and stem fasciations—do you know what these are and how they are formed? Welcome to the huge and fascinating world of plant galls and other abnormal growth patterns. Come out with Docent Naturalists Frances Reneau and Helena Cohen on this leisurely-paced exploration along the Salamander Springs, Myotis, Beaver, and other trails to learn how to spot spined turbans, red cones, pink bowties, and yellow wigs hiding in plain sight on some of your favorite plants. Bring a loupe if you have one.

Where to Meet

Meet at the Alma Parking Area.  From Highway 17 take the Bear Creek Road exit, opposite Lexington Reservoir. (From southbound Hwy. 17, exit the highway and go under an overpass; road will curve right to a stop sign at Bear Creek Rd., turn left. From northbound Hwy. 17 exit highway and cross the highway via the overpass on to Bear Creek Rd.) Travel 1.0 mile from Hwy. 17 on Bear Creek Rd., as road curves left there will be a pedestrian crosswalk, turn left into the parking lot immediately after the crosswalk.

To ensure your experience on a docent naturalist outing is enjoyable please review these activity guidelines.

For more information about trail characteristics for this event, check out the Midpen Trail Explorer app. To learn more about ADA accommodations for events, or make an inquiry with the ADA coordinator, visit our Accessibility page.

If your activity requires registration, please be sure to cancel your reservation (from your confirmation email) if you are no longer able to attend so others can participate.

After your participation on a guided activity please share your feedback — your input is meaningful to our volunteers and program staff – thank you!