Mount Hamilton Driving Tour

Leader: Terry Gosliner

Please sign the Marin Chapter Waiver for 2024 if you haven't already done so.

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. 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. This will be a full day trip. We will make several stops along Mt. Hamilton Road and do a bit of walking at a couple of places. Parking at the various stops along the road up Mt. Hamilton is limited. We will try to maximize the number of people in the cars, so there is enough space for all the cars at each stop up the mountain and down the other side into 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.

Bring water, lunch, snacks, and rain gear.
Rain cancels.
Email Terry with any questions. tgosliner@calacademy.org
Text for day-of-trip questions or issues: 415 302-9667