MANZANITAVolume 18, Number 3 • Published by the Friends of the Regional Parks Botanic Garden • Autumn 2014 Phenomenal Phenology by Glenn Keator, PhD Golden eardrops (Ehrendorferia chyrsantha), a fre-following perennial, bloomed in the burn area on Mount Diablo during the frst spring after the 2013 Morgan Fire. Photos: Rosie Andrews re you an avid gardener? A wildfower enthusiast? A patterns in the sway of events, you’re engaged in phenology, a study dedicated birder? Then you are engaged in phenology, that most likely originated with the frst peoples, whose lives were Athe all-encompassing phenomenon of observation—the interlinked by necessity with the ebb and fow of the natural world. climate, the rhythm of the seasons, the minutiae and grand sweep Phenology is the study of periodic events in the life cycle of a of change, in other words, the ways of nature. Whether it’s noticing plant or animal and how those events are affected by variations in when those poppy leaves frst emerge during the rainy season, when climate and local habitat. When I teach people to identify plants, brodiaea blossoms open, when veggies and fruits are ready for I’m engaging in a very different view of things—a short window harvest, which pollinators visit in March, or any of the numerous in time of how a particular fower looks in bloom, but only a short Continued on page 3 MANZANITA Friends of the Regional Parks Botanic Garden Volume 18, No. 3 Autumn 2014 Advisory Council Rosie Andrews, Managing Editor Sue Rosenthal, Editor Glenn Keator, Chairman Neil Havlik Emerald Canary, Graphic Designer Ruth Bancroft Ted Kipping Gert Allen Russ Beatty Bart O’Brien Kim Hamilton Maggie Ingalls Rolf Benseler Bob Raabe Jean Jackson Janet Cobb Roger Raiche Glenn Keator Susan D’Alcamo Mary and Lew Reid Shoshana Wechsler Stephen W. Edwards Warren Roberts Manzanita, a quarterly newsletter of the Friends, and The Four Barbara Ertter Jake Sigg Seasons, an annual publication of the garden, are benefits of Mike Evans Nevin Smith membership. The nurseries listed below offer discounts to Friends. Phyllis Faber Lew Truesdell These participating nurseries are sources for native plants. Wilma Follette Richard Turner Annie’s Annuals and Perennials (510-215-3301), Roman Gankin Stewart Winchester 740 Market Avenue, Richmond, www.anniesannuals.com Katherine Greenberg Bay Natives (415-287-6755), 10 Cargo Way, San Francisco, www.baynatives.com Board Members Berkeley Horticultural Nursery (510-526-4704), 1310 McGee Gert Allen, President Glenn Keator Avenue, Berkeley, www.berkeleyhort.com Rosie Andrews Jim Nybakken California Flora Nursery (707-528-8813), Somers & D Streets, Linda Blide Anne Olsen Fulton (north of Santa Rosa), www.calfloranursery.com Bob Case Sue Rosenthal Central Coast Wilds* (831-459-0655), 336 Golf Club Drive, Santa Ron Clendenen John Rusk Cruz, www.centralcoastwilds.com Luke Hass Andrew Walmisley East Bay Nursery (510-845-6490), 2332 San Pablo Avenue, Berkeley, www.eastbaynursery.com Garden Staff Larner Seeds (415-868-9407), 235 Grove Road, Bolinas, Director: Bart O’Brien www.larnerseeds.com Supervisor: Joe Dahl Gardeners: Liz Bittner, Cat Daffer, Mostly Natives Nursery (707-878-2009), 27235 Hwy. 1, Tomales, www.mostlynatives.com Don Fuller, Michael Uhler Senior Office Assistant: Teresa LeYung-Ryan Native Revival Nursery (831-684-1811), 2600 Mar Vista Drive, Aptos, www.nativerevival.com Interpretive Student Aide: Ashika Narayan *wholesale; please call ahead Friends members gain free admission to participating gardens GIFTS: Donations to the Friends are welcome and may be through the American Horticultural Society’s Reciprocal Admissions designated for special projects or given in honor or in memory Program (http://ahs.org/gardening-programs/rap/find). Contact the of someone. individual garden to verify this benefit. ENDOWMENT: Contributions to the Regional Parks Botanic • Garden Endowment Fund assist in providing financial security MEMBERSHIP for the garden. Your membership in the Friends of the Regional Parks Botanic Garden supports the important work of the garden in educational Please make all checks payable to the Regional Parks Foundation; programs, conservation, and horticultural experimentation. Funds note whether for Friends membership, gift, or Endowment Fund; raised by the Friends help provide long-term financial security for and send to: the garden as well as new facilities and programs. Friends of the Regional Parks Botanic Garden P.O. Box 21074, Crestmont Station, Oakland, CA 94620 MEMBERSHIP CATEGORIES Student/Senior/Limited Income: $20 The Board of the Friends generally meets at the Visitor Center Individual: $35 in the Regional Parks Botanic Garden the second Wednesday of Family/Group: $50 the month at 10:00 AM. All members are welcome. Call ahead to Special: $100 or more verify meeting date and time. FOR INFORMATION • About the Friends and membership: 510-544-3169, [email protected] www.nativeplants.org About becoming a garden volunteer or docent: 510-544-3169, [email protected] Continued from page 1 MANZANITA Autumn 2014 window. The truth is that to truly know a plant, you usually warm weather, unusual droughts in winter, need to observe it through all of its manifestations or prolonged times of frost. from seed to mature plant: from emerging from its Factors infuencing fowering are perhaps better roots to leafng out, from leafng out to blooming, understood, the main determinants being tempera- and from blooming to setting seed. Then and only ture and day length (technically, plants sensitive to then will you truly know a particular plant. Rosie Andrews Two very practical applications of phenological studies are learning when plants come up and bloom in the garden and how to predict a good wildfower year. The second is far more challenging; the frst, something you can truly embrace with careful observation. For plants that are dormant in winter, factors that infuence emergence include day length, temperatures and temperature fuctuations, and rainfall. As far as we know, dormant plants have no way of relating to day length (while fower- ing often depends on it), but the combination of temperatures, their fuctuations from night to day and season to season, and availability of water are useful clues to use in making accurate predictions. Some plants seem to be more sensitive to one set of factors, while others are affected by a different set. For example, rainfall is especially important in germination of seeds of desert annuals, and early rains may bring about premature germination, which spells doom to the early germinators when followed by a drought. Bigger, longer-lived plants Mariposa tulip (Calochortus venustus) on Mount Diablo may also be infuenced by rain, since root develop- ment underground is prolonged and activated by day length actually measure the length of the dark suffcient soil moisture. period or night). You’ll soon learn which plants are Temperature variations are more diffcult to reliably “on time,” blooming on schedule from year interpret: Unseasonably warm weather in winter, to year despite other environmental conditions. for example, can promote early appearance of These are the plants that rely solely on day length. new shoots, but if a signifcant frost should follow, You’ll also learn that other plants bloom less pre- the growth of the plant that year may be greatly dictably, and in some years their blossoms appear reduced. Many plants are sensitive to variations in much earlier than others. These are the plants sensi- air temperature from day to night and night to day, tive to temperatures. Again, keeping careful records but for others, the important factor is how warm helps the gardener plan, since color in the garden is or cold the soil is. Many species, like the milkweeds a valuable asset and coordinating the color scheme (Asclepias spp.), don’t respond to warm temperatures may become an important parameter of design. until the soil itself has become suffciently warm. Now let’s turn to nature’s roulette: the timing of Most plants from permanent wetlands are winter wildfower displays in spring and summer. While dormant, their new growth appearing mostly in late much is known about the approximate bloom time, spring to early summer. An example of this is the accurate prediction can be damnably diffcult. For re-emergence of cattail shoots (Typha spp.) after a those of us who lead feld trips and hikes, the ability long winter rest. to predict becomes particularly critical. The frst Because there is so much interaction between and foremost question is, will it be a good year? The climate and other environmental factors, the best second question is, when will the fower color peak? policy for the gardener is to keep a log from year to You would think that after years of observations, year, recording rainfall times and amounts as well making predictions like these would be relatively as temperature changes, especially periods of un- straightforward. If we have a large amount of 3 Evidently, those later rains fred up the metabolic processes of germination, growth, and sprouting, while earlier on the plants had been on emergency rations. Could this be a response to the threat of death from lack of water (with some help from fertilizing ash from the fre), promoting growth when conditions suddenly change? Even so, I can only guess the reasons. Nor can I say why my own garden seems lusher than ever, which brings to mind the idea that not just the amount of water but the way it is distributed in time may play a role in garden vigor. To put it another way, rain may be a better promoter of growth than water from a hose, or a drip system, or a gray water source. Obviously, we still have a lot to learn about these phenomena, and the bottom line is to record the data each year and learn to interpret it.