My Gall Friday

Friday, April 24, 2026

9:00 am - 12:00 pm

Long Ridge Preserve

Approximate Total Miles

3.5

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 Hickory Oaks, Ward Road, and Ranch Spring 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 Hickory Oaks Roadside Parking; 5.1 miles south of Page Mill Road or 1.3 miles north of Highway 9 on the west side of Skyline Boulevard.

Link to Google Map

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!