Doug's Mountain Journal
A Chronicle of Natural History on San Bruno Mountain

Doug Allshouse has been writing his seasonal Mountain Journal for many years. It appears in the quarterly newsletters of the Yerba Buena Chapter of the California Native Plant Society (CNPS). We are very pleased to share his reflections on the natural history of the Mountain. Together with David Nelson, he is writing San Bruno Mountain: A Guide to the Flora and Fauna. The book will be published by Heyday Books in 2022.

And so it was declared, that on Monday, May 4, 2020 the park would reopen after 37 days of darkness, and Mountain magic would finally be unleashed. A ranger descended from the summit with a tablet of new commandments and affixed them to the chain-link fence by the Crocker Avenue gate for all the visitors to see and obey. And they did, and the spirit of the Mountain rejoiced once again.

Okay, it is a bit melodramatic, but I confess to a bit of rote boredom doing laps on Crocker Avenue and looking at the orange plastic fencing across the park gate with the subtle message—KEEP OUT. The only education I got in those 37 days was the knowledge that four vehicles parked on Crocker were housing overnight Uber/Lift drivers and homeless people. I was ecstatic to get back to the wilderness.

One important reason why I was so happy to get back onto the Mountain was to finally start work on eradicating an invasive plant that required an approved Site Activity Review, and it was suspended during the closure. SARs are mandatory when dealing with an active Habitat Conservation Plan. It all started in May 2019 during the annual SBM Natural Resources Management Committee field day during a visit to the reintroduction site of the Bay Checkerspot butterfly. While we were standing on the Ridge Road listening to what had been accomplished, I looked down and found a patch of narrow-leaved clover (Trifolium angustifolium). It was too late in the season to pull the plants so I applied for a SAR in early March 2020 and waited for approval. Less than a week after approval the park closed.

On May 5 I went out on the Ridge Road and began pulling the clover. Due to the cold, skimpy rainy season the clover was weeks behind last year’s crop. On May 19 I returned and with the help of Dr. Stu Weiss of Creekside Science we pulled well over 3,000 clover plants and fistfuls of rattlesnake grass (Briza maxima). We retired to the shelter of a bluff at the top of Army Road, a PG&E access road, to eat lunch and shared our space with a few Callippe Silverspots. Then we headed to East Powerline where we checked out the area that burned last October. One of the projects that Creekside completed was planting multiple sites of summer lupine (Lupinus formosus) a key larval host plant of the Mission Blue butterfly. He was very happy to see newly germinated plants in those sites. Along the way we discovered some unusually robust native brownie thistles (Cirsium quercetorum). Generally about 10-15 cm tall, these plants were a humongous 25-30 cm tall. It is not uncommon to see giant versions of generally small plants after a fire, given the added minerals, particularly phosphorus, which fires create.

One thing that makes life more interesting is learning new things, especially when that lesson flies in the face of generally accepted theories. We associate super blooms with extremely wet years; however this year’s rainfall totals (15.59”) were about half of last year’s (29.68”). This year had 6 more days of precipitation and had 13 more days (73 vs. 60) and 0.54 more inches of moisture from fog. That’s important for those plants that practice foliar uptake, taking in moisture through their stomata. Maybe that was the reason why farewell-to-spring (Clarkia rubicunda) bloomed just as profusely this year as last year. In vain, we ask those questions for which there are no answers. Mother Nature throws us curveballs, sliders and high heat and we just keep swinging and missing.

Breaking news from the lower Colma Creek Bridge on the Bog Trail: About five years ago a patch of false lily-of-the-valley (Maianthemum dilatatum) established itself at the foot of the bridge. A more mature patch has existed for decades about 15 feet away and this year it produced seven blooming spikes, up from one last year. The newer patch finally had its first spike this year. This species is fascinating because it typically produces crowded carpets of heart to kidney-shaped leaves with long petioles. In a few rare cases a leaf petiole will produce a second stem, a peduncle, with a slightly smaller terminal leaf. Just below that leaf’s base a pedicel with a small terminal leaf-like bract produces a flowering spike. The structure of the flowering plant is intricate and complicated but very beautiful. The other good news is that on the other side of the bridge a renaissance is taking place. Last year at about this time the bridge was mostly rebuilt with some added construction. A drainage ditch was dug and in the process several low clubrush plants (Isolepis cernua) and fragile ferns (Cystopteris fragilis) were destroyed. They are coming back and with a little luck, a lot of weeding, and care they will reestablish themselves.

It is quite invigorating to spend a few hours on a sand dune that is 80,000-125,000 years old, especially when it is two miles inland. A few Yerba Buenos snuck out to the Daly City Dunes on the first Saturday in June festooned with facial masks and social distancing to catch a glimpse of the wildflower show. Of special interest were four species in the Evening Primrose family in the genera of Camissonia and Camissoniopsis (local rarities), and blue beach lupine (L. chamissonis). Camissonia, Camissoniopsis and chamissonis are all derivatives of the last name of Adelbert von Chamisso, a German naturalist who along with Johann Friedrich Eschscholtz was part of the Kotzebue expedition aboard the Russian ship Rurik, which visited the SF Bay in 1816.

The real stars were two rare and endangered herbs, San Francisco spineflower and SF lessingia. The spineflower was blooming in large carpet-like communities and the lessingia was just beginning to bloom. A visit to the dunes in mid-July provided a splashy show of thousands of tiny yellow flowers. Across Colma Canyon lies Boneyard Quarry, which was awash with splashes of bright pink farewell-to-spring blooming in the scree. This steep rock-studded landscape is also home to mass blooms of SF collinsia, California gilia, and stonecrop (Sedum), the larval host plant of the endangered San Bruno Elfin butterfly.

From late June through July, poison oak starts losing moisture and that stress causes the plant to draw down its chlorophyll resulting in a riotous display of color in wild ranges of red. I’m sure that I mention this every year but, quite frankly, I am smitten with this diverse woody bush. I have photographed this plant along with creek dogwood more than any other plants on the San Bruno Mountains. The diversity of colors and textures of their leaves and berries intrigue my inner soul. There is one spot on the Bog Trail where poison oak interacts with coyote bush, coffee berry and lizard tail. This year an inflorescence of lizard tail decided to become the star of the show as it stretched above the poison oak’s bright red leaves with a glorious splash of electric golden yellow, a nature photographer’s dream.

This was a good year for Swainson’s Thrush around Fog Forest and the Bog. A plethora of ethereal songs in spring titillated my ears, as the songs of most thrushes generally do. I heard a lot of calls from adults hidden deep in the willows surrounding Colma Creek. Trying to see one in the maze of branches and leaves is a task for the truly insane, but every once in a great while, dumb luck wins out. As I was walking away from the upper Colma Creek Bridge a first-year thrush was perched on a willow branch at the trail’s edge long enough for me to get my binoculars on it. Adult Swainson’s are extremely secretive and not as mellow as the Hermit Thrush is in the fall and winter.

This has been a most unusual sunny and mild July so far. With the exception of July 10th there had been no fog or drizzle until the 20th-22nd, with the sun appearing by late morning. The only exception was a miserably foggy 21st, a preview of our true summer up here, high on the Guadalupe Hills. The one truth I have learned in the 42 years of living up here is that the nicer it is in July or August the nastier it will be in September. You will have to wait until the autumn edition to see if my hunch comes true.

See you on the Mountain…

Banner photo caption: Lizard tail, or woolly sunflower, growing through poison oak