Today’s Glimpse from the Field is another edition of David and Doug's San Bruno Mountain Rare Plant Alert emails, from May 10th, 2016. David Nelson and Doug Allshouse are on the Mountain every Saturday in their search for interesting, rare and endemic plants - this ongoing research is the basis for their upcoming book. Together they are writing "The Natural History of San Bruno Mountain", a long-needed and detailed natural history of the Mountain. The book will be published by the California Native Plant Society.
David Nelson, aside from being a surgeon, is a devoted Mountain Watcher and amateur botanist. Doug Allshouse is an expert on San Bruno Mountain flora & fauna who has studied the Mountain for 38 years. They send out regular SBM Rare Plant Alert emails to interested persons. David can be contacted at email@example.com and Doug at firstname.lastname@example.org. Contact David if you would like to be on the SBM Rare Plant Alert List. (All photographs by David Nelson unless otherwise attributed)
During the last four weeks we set our all-time record for new and important discoveries on the Mountain! We have three amazing botanical finds to report to you.
The greatest discovery was by our colleague and scout, Mark Sustarich: Silene verecunda! This diminutive relative of Silene scouleri has eluded our search efforts for two years. Even joint searches with David Schooley and Mark Sustarich, both of whom had been shown Silene verecunda by Elizabeth McClincock herself, failed to find any plants. (Note: Elizabeth McClintock authored the definitive book on San Bruno Mountain flora in "A Flora of the San Bruno Mountains", first published in 1968 and the revised version published in 1990.)
There has been some confusion in differentiating the two Silene species. S. verecunda had reportedly been seen in 1994 by TRA Environmental Sciences (a biology consulting company working at that time with San Mateo County (SMC), and by Joe Cannon in 2008, but no specimens had been collected and no photographs taken that we are aware of. Based on Doug's interviews with both TRA and Joe Cannon, there was some doubt about the accuracy of these sightings. Plants that clearly were S. scouleri had been identified as S. verecunda, and it was easy to see why: neither McClintock nor Jepson were very useful in their descriptions. Therefore, a group of us (Lech Naumovich, Cristal Niederer, Doug Allshouse and David Nelson) went to the herbarium of the California Academy of Sciences to clarify the differences. Studying the San Bruno Mountain specimens (including some collected by Alice Eastwood and by Elizabeth McClintock), we developed a six-point differentiation, and so armed, we scoured the hills in the last places where it was known to be seen. No luck.
Mark was not discouraged by the hours of disappointment, hope sprang eternal, and he kept up the search. Finally, on April 10, 2016, Mark found 2 plants that he was sure were S. verecunda. He contacted Doug, who joined him the next day and confirmed the ID based on our six points. They found 36 plants. The next Saturday the three of us worked together and found 82 plants. The plants are rather petite and amazingly hard to see, even when you are looking directly at them. We measured each, photographed them against a cm grid, and counted the stalks, buds, and flowers. All the information was given that weekend in Excel format to Ramona Arechiga, SMC Parks Natural Resources Manager, as well as all the photographs.
The area where the plants are located is off established trails, in critical butterfly habitat, and the soil is sensitive to erosion. To protect the plants, the County has asked that the location remain undisclosed. We appreciate your cooperation in preserving this rare plant listed on the CNPS 1B.2 List of Rare and Endangered Plants.
The second discovery has an equally thrilling story. To understand the story, a bit of background. Jim Roof, the legendary San Bruno Mountain explorer and founder of the East Bay Regional Parks Botanical Garden, found a new manzanita in May of 1962 and named it after one of his chemistry professors at Berkeley, Leo Brewer, PhD - Arctostaphylos uva-ursi forma leobreweri. Unfortunately, in September of 1964, a fire swept up the ridge where the Arctostaphylos uva-ursi forma leobreweri grew, burning it to the ground, and it never re-sprouted. After who knows how many thousands or millions of years of surviving fires, it was lost from the Mountain within two years of its discovery, probably due to higher fuel loads from both lack of grazing and lack of the historic fire regime used during Native American times.
But as I said, Jim Roof was a nurseryman and the founder of the East Bay Regional Parks Botanical Garden. So he'd taken cuttings back to his botanical garden! After his death in 1983, Steve Edwards, Roof's successor at the garden, gave some of the plants back to San Bruno Mountain Park staff. With the assistance of Roman Gankin, of the SMC Parks, and Paul Reeberg, co-author with Elizabeth McClintock of "A Flora of the San Bruno Mountains", three specimens were planted in 1987. They are still growing, in a protected location. The East Bay Regional Parks Botanical Garden also gave the County two other lost SBM natives, Maianthemum dilatatum (false lily of the valley, or two-leaved Solomon's seal, planted along the Bog Trail) and Tanacetum bipinnatum (dune tansy, planted in the mini botanical garden along Old Guadalupe Road Trail, near the main parking lot; see more on this later in this feature).
We return to our story...
Just as explorer Gaspar de Portola found San Francisco Bay by accident while stumbling around California looking for Monterey Bay, our friend and colleague Lech Naumovich set out to study the Arctostaphylos uva-ursi forma leobreweri, got lost, and amazingly found another stand of leobreweri! He was so excited, he ran up the Mountain and all the way along the Ridge Trail to tell Doug, who was there to meet him. Doug and I hiked back out there May 30, 2016 and found the two plants.
As Doug and I inspected the plants, we noted that they were located far from the original place where Jim Roof discovered the original specimen, so the question arose: how did they get here? The two plants are doing well, about 3 m across and sending branches out, spreading even further. Doug and I searched the area, did not find any further plants, but did find the answer to the mystery. What is the answer? Tune in to the next issue of the SBM Rare Plant Alert and find out!
The third discovery was made by another of our scouts, Judy Hiramoto. She is an artistic photographer who is writing an art book about San Bruno Mountain and illustrating it with her own photos. She was exploring a very ordinary gravel ridge right off Radio Road, a place so ordinary and bare that no reasonable person would explore it. She found a fern that she could not identify. So she sent a photo to us and asked if we could identify the fern. Amazingly, the "fern" was none other than Tanacetum bipinnatum - Dune Tansy! While not a rare plant, it is locally rare and has a great conservation history behind it.
The Dune Tansy is the third plant that San Mateo County Parks received from the East Bay Regional Parks Botanical Garden! We had known that specimens from the garden had been planted in two locations. One location was along Radio Road, near the location where it was last seen before being killed under a pile of debris that had been illegally dumped there, and some were planted at a location near the main parking lot. The ones growing near the parking lot are surviving, but are struggling with invasive plants. However, no one we know had seen the plants that were placed along Radio Road, and we thought they had died. Judy found our long-lost second planting of dune tansy. (It should be noted that Bart O’Brien, the head of the East Bay Regional Parks Botanical Garden, thinks that the dune tansy that they gave to the County is NOT from San Bruno Mountain, but likely from Sunset Heights.)
What a wild time to be a botanist on San Bruno Mountain! Our thanks for all of you who are alerting us with your discoveries. Tune in next time for the solution to the mystery of the Leo Brewer’s Manzanita!
See you on the Mountain!
David & Doug