Leaders: Doug Allshouse and David Nelson California is the world center of manzanita diversity; 104 of 105 manzanita species are found within the California Floristic Province. Over half of the species are centered in the narrow coastal region between Mendocino and San Luis Obispo counties. This suggests that the genus evolved in the western part of North America, and evidence dates them as far back as the Middle Miocene (15-11 million years ago) during a time of global warming. San Bruno Mountain is ground zero for glandular manzanitas. Of the seven species and forms here, four are endemic. On this field trip we will see three endemics; San Bruno Mt manzanita (Arctostaphylosimbricata), Pacific manzanita (A. pacifica), Leobrewer manzanita (A. uvaursiforma leobreweri) and one rare and one common manzanita; Montara Mt manzanita (A. montaraensis) and evergreen manzanita (A. uva-ursiforma coactilis). Manzanitas are not easy to identify and may seem intimidating, but thanks to a recent publication the job is much easier. If you have a copy of the Field Guide to Manzanitas by Michael Kauffmann, Tom Parker, and Michael Vasey, bring it along. If not David and Doug have created a quick and easy foldout guide to help you identify the San Bruno Mountain manzanitas. We will also see other plant taxa along the way. Due to the sensitive nature of this off-trail adventure we must limit this outing to 15 people. If you want to attend this limited
field trip, please email Doug to reserve your space and confirm our meeting place. Bring a lunch and a 10-power loupe. Heavy rain postpones to February 24. There is a $6 cash fee payable at the ranger kiosk. Contact Doug at [email protected]
, call or text 415- 269-9967.