Mt. Hamilton

Driving Tour with stops and short walks

Sunday, May 5, 2024 8:30 am to 5 pm      Leader: Terry Gosliner

Please sign up for this field trip on Meetup.

Please sign the Marin CNPS Waiver for Marin Chapter 2024.

Mt. Hamilton is the highest peak in the Bay Area at 4,265 feet and is part of the Diablo Range that extends from Mt. Diablo south to Orchard Peak in Kern County. This part of the inner Coast Ranges is typically much drier than our outer coast ranges in Marin. Mt. Hamilton has a great variety of habitats including many that are not found in Marin. As a result, it has a rich flora and is home to many species not found in Marin County.

Streptanthus callistus Terry Gosliner

Showy flowers like Lindley’s blazing star (Mentzelia lindleyi) and the wind poppy (Papaver heterophyllum) are some of the spring beauties we will likely encounter. Some of the plants are restricted to Mt. Hamilton and endemic to the mountain such as the Mt. Hamilton Lomatium (Lomatium observatorium) found only around Lick Observatory and the Mt. Hamilton jewelflower (Streptanthus callistus) found in Arroyo Bayo. We will look at native herbs, trees, and shrubs in this picturesque area.  After the LNU Complex Fire burned over much of the area in 2020, we may find many changes from our last field trip there in 2017.

Lomatium observatorum Terry Gosliner

This will be a full day trip. We will make several stops along the Mt. Hamilton Road and do a bit of walking at a couple of places. Additionally stops will be made on the east side of Mt. Hamilton at Arroyo Bayo and Del Puerto Canyon.

Terry Gosliner is a CNPS member and a Curator in the Department of Invertebrate Zoology and Geology at the California Academy of Sciences where he specializes in the evolution and systematics of nudibranchs (sea slugs). While his research focuses on marine biology and often takes him to coral reefs in the Philippines, he has a life-long passion for native California plants. As a child he grew up in Marin and explored the plants of the Bay Area from an early age.

Directions: Meet at the Manzanita Park & Ride, Mill Valley (8:30 am). As parking at the various pullouts along the Mt. Hamilton road is limited, we will try to maximize the number of people in each car by carpooling. We will limit to four vehicles.  Expect to return to the Manzanita Park & Ride at approximately 5 pm.    Maximum 16 participants.

Bring: Water, lunch, snacks, and rain gear.   Rain cancels

Email Terry with any questions. 

Text for day-of-trip questions or issues: 415-302-9667