Field Trips

CNPS- Yerba Buena Natural History Walks:

Please note: Statewide CNPS is requiring signed waivers from event participants.

When noted, field trips require participants to sign online or paper waivers

And special thanks to our dedicated field trip leaders!

Upcoming Field Trips 2023




March 2, 2024 from 10am-2PM

San Bruno Mountain, South Slope

Leaders: Chuck Heimstadt and Loretta Brooks

Join Chuck Heimstadt and Loretta Brooks on a field trip to explore the less visited south slopes of San Bruno Mountain. With its bright landscapes of large grassland areas critical to resident endangered
butterflies and some locally rare plants on the CNPS watchlist, such as coast iris (Iris longipetala) 4.2, coast rock cress (Arabis blepharophylla) 4.3 and San Francisco wallflower (Erysimum franciscanum) 4.2,
we may also see the coast onion, Allium dichlamydeum, and may blooming Mission Blue butterfly host plants, silver bush lupine, Lupinus albifrons var collinus, and California golden violets, Viola
pedunculata. In addition, will see Niebla lichen occurs only in the fog belt of the California coast from Mendocino to Baja.

Since there are only fire roads and weeding trails on this side of San Bruno Mountain, you will be walking on steep, rocky slopes that can be difficult to maneuver. So please be sure to wear sturdy
footwear as this area is only for the really adventuresome. We should have time to stop at the top, so bring a sack lunch. Restrooms are only available in the
parking area.

Space is limited. To check availability, please email directly Loretta and Chuck at:

Details of the meeting location will be sent to participants closer to the day of the hike. Rain cancels and leaders will alert you if this is the case before that morning. The group will be limited to 10 people, we
will need email addresses to be able to contact the participants. As always on San Bruno Mountain, be prepared for sun, wind, or cold, so wear layers.

Participants will need to sign a waiver at the location where we meet.


Saturday, March 23, 10am-1pm

San Bruno Mountain: Buckeye Canyon

Leader: Doug Allshouse


Buckeye Canyon offers a habitat not common to most of the mountain. Excessive rainfall in the November and December of 2022 set the stage for a tragedy. On December 31, 2022 an atmospheric river dumped over six inches of rain in a continuous 12-hour period and caused a horrific landslide that changed the geology of the canyon from top to bottom. Now—over a year later— the canyon is beginning to heal itself, and with some outstanding stewardship it is bending to mostly native species. We’ll visit an Ohlone shellmound then immerse ourselves in a riparian forest of buckeye, bay and oak trees as well as toyon, hound’s tongue, chaparral currant, blue elderberry, ferns and gentian. We will also see brittleleaf manzanita (Arctostaphylos crustacea subsp. crustacea). If conditions are favorable we will take a trail up the north ridge to Owl Canyon and traverse a trail down spring grasslands loaded with wildflowers. Bring a lunch or snacks. This walk is limited to 15 people. Contact Doug at to register and get directions to the meeting place. Heavy rain cancels.

Participants should sign this waiver


April 13, SATURDAY 10am- 2pm

San Bruno Mountain: Summit Trail

Leader: Doug Allshouse


The Summit Trail is a very popular and spectacular 3-mile loop that stretches over the northern portion of the Mountain and is the most species-rich trail. It passes through a logged eucalyptus forest and descends past active seeps until it reaches April Brook. We’ll see horsetails, fringe cups, iris, coast rock cress, a club-rush, and at least five ferns. From there we head up to Bitter Cherry Ridge with rocky outcrops covered with fog lichens and views of the ocean and the Colma Canyon dunes. If we have time, we’ll descend to the parking lot through Cable Ravine. Otherwise, we’ll bail out at Battery Road 59 and descend Radio Road. There is a $6 entrance fee (cash, credit/debit card) payable at the pay station. Bring a lunch and layers of clothing because, due to the marine influence, you never know what to expect. This field trip will be limited to 15 persons. Heavy rain cancels. Contact Doug at to sign up and get meeting instructions.

Participants should sign this waiver