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 seasonal reflections on the natural history of the Mountain. Together with David Nelson, he is writing "The Natural History of the San Bruno Mountains", a long-needed and detailed natural history of the Mountain. The book will be published by the California Native Plant Society.
The wind is howling and it’s pouring right now as the first front of a cold storm blitzes the Alemany Gap and threatens to pick up some tropical moisture down south and soak the coast. The ski resorts are wearing a Cheshire-Cat grin with the potential of snow measured in feet. With wind gusts in the 40-60 mph range predicted, I have secured the funnel-shaped lid of my rain gauge with a couple strips of duct tape to prevent it from being blown off. Yes, it happened once with an unsecured lid but luckily, I found it nestled against a fennel plant down the hill. Storms and a few wet foggy days from November through mid-January have given us 10.61 inches of rain. The recent January storms have pumped up Colma Creek quite a bit. We’re ahead of last year, but far behind the super-soaking 2016-2017 rain season that gave us a bit more than three feet of rain.
Fog plays a huge part of the mysterious beauty that encompasses the Mountain especially in the morning. It was on one of those December mornings that thick fog made it difficult to see very far. Ahead of me on the Bog Trail was a creature, but all I could see was a bouncing white patch—perhaps a brush rabbit tail or the rump of a flicker I thought? Thirty seconds later I heard the wicka-wicka-wicka call of a flicker...thank you, mystery solved!
Winter, as I have stated many times in my Journals, is my second favorite season. It’s the season of renewal, a celebration of the birth and rebirth of our native plant species. It’s also a time of a dichotomy among our large berry-producing shrubs. Wax myrtle produces the most unusual and fat-giving berry. It’s barely a berry at all but rather a bumpy drupe of black wax surrounding a seed. By January there is nary a berry to be seen because the birds have stripped the branches of the high-energy fruits that will power our feathered friends through the cold of winter. Wax myrtle prefers cool, moist coastal habitats near creeks or shade. The dichotomy is that about the time the wax myrtle has given up its fruits a few other shrubs are coming to life to supply food to our flitting balls of feathers.
Ribes is the genus of gooseberry and currant shrubs and the early-blooming Chaparral or California Black currant has already broken out with its coarsely-wrinkled, lobed leaves and hot pink flowers. This deciduous perennial shrub lacks the nodal spines common to the gooseberries. The fragrant flowers are a great winter nectar source for hummingbirds and by March the shrubs should be laden with striking purple fruit. It is edible although not overly delicious, but the birds will probably get to them first.
There are two species of elderberry on SBM that differ greatly in their choice of habitat. Coast red elderberry is awakening from dormancy in January with bursts of bright green stems and leaves. It prefers cool, moist habitats and is one of the few native shrubs that thrives under a eucalyptus canopy. The inflorescence is a dome-shaped cluster of dark red flowers that turn creamy-white before becoming small green berries that turn bright red at maturity. Cedar Waxwings and thrushes love these berries, but the biggest glutton of all is a hungry Band-tailed Pigeon; known to practically strip a small elderberry bush of its bounty. The blue elderberry blooms slightly later than the red elderberry and, even though a sibling of red elderberry, it seems to prefer a warmer and drier climate. The blue elderberry fruit is delicious and potable to a human’s stomach whereas red elderberry fruit needs to be cooked to prevent an upset stomach. The green parts of both plants are mildly poisonous because they contain cyanogenic glycosides.
Toyon is a perennial shrub, native to the southwest corner of Oregon through California to Baja California. It varies in height from 2-8 m tall and is extremely drought-adapted with tough leathery leaves. In the summer it has small white flowers that give way to clusters of greenish berries in the fall that mature into yellow and eventually bright red pomes that last well into winter and are highly prized by birds. Long before the advent of planting pyracantha and cotoneaster for floral trimmings at Christmas, toyon berries were gathered commercially and sold. It is often called California holly because the shrub is holly-like and showy, especially in winter with its berries. Toyon is so abundant in the Los Angeles Basin that the name Hollywood Hills came about. It is one of the few native plants from which honeybees make honey. Interestingly toyons that grow on the very north and northwest part of SBM do not produce berries, perhaps because of the cooler climate. They are spectacular in the fog-sheltered Brisbane canyons and along Bayshore Boulevard from Brisbane to South San Francisco.
January through February is the optimum window to see manzanita flowers. San Bruno Mountain has five species that live here; two are endemic, and the most common species in the world has two forms that are endemic; four endemic manzanitas in four square miles is mighty impressive. That sounds like a discussion for another Mountain Journal.
So many perennial species are waking up from their dormancy and the annuals are beginning to germinate. We often forget that the first three months of the year are truly spectacular with days of cold, rainy weather followed by breaks of sunny, warmer conditions. Everything seems more interesting. The grasses begin to add a green sheen to the landscape, the scrub appears more vibrant since their foliage has been scrubbed of dust by the rain, and, by gosh, a few wildflowers have appeared. It’s a great time to explore the wild wonders and inhale the cool, sweet air. You’ll be glad you did.
See you on the Mountain...