View southeast from block F8 of Griffith Park (see Figure 2) showing downtown Los Angeles (at right) and the Los Angeles River (center). RARE PLANTS OF GRIFFITH PARK, LOS ANGELES by Daniel S. Cooper
ising more than a thousand feet ged interior is still surprisingly wild, such landmarks as the Griffith Ob- off the floor of the Los Ange- owing to both its steep topography servatory and the Los Angeles Zoo, les Basin, Griffith Park divides and lack of established trails. none of which sustained damage. the eastern San Fernando Val- Just a few weeks earlier, on March Rley from the coastal plain of Los 30, an arson fire had swept up to- Angeles and protects more than WILDFIRE PROVIDES ward the northwestern corner of the 4,000 acres of rugged slopes and IMPETUS FOR NEW park, burning a large area of high- canyons at the eastern end of the RESEARCH elevation chaparral atop Cahuenga Santa Monica Mountains. Although Peak, the highest point in the east- portions of the park are heavily used, On May 8, 2007, an arson- ern Santa Monica Mountains. While with golf courses, grassy picnic ar- caused wildfire burned about 20% these fires radically altered portions eas, and other attractions situated of the park, essentially the entire of the park’s vegetation—at least mainly at the park’s borders, its rug- southeastern corner, threatening temporarily—their more lasting
18 FREMONTIA VOLUME 38:4/39:1, OCTOBER 2010/JANUARY 2011 contribution may have been the in- because of its rugged topography Mountains. Included in this list were creased awareness they elicited from and the fact that most readily acces- both CNPS rare taxa (California local conservationists and city staff sible hiking areas (mainly fire roads) Native Plant Society 2010), as well alike, most of whom had never ex- have been degraded by weed abate- as a group of species we felt were plored the park. Suddenly, the park ment practices and non-native veg- significant, either because they are seemed like a worthy subject of im- etation. rare in the region, or because if mediate ecological exploration, per- found, they would represent dis- haps because it was almost com- SURVEY LAUNCHED junct occurrences from populations pletely reduced to ash-covered farther west in the Santa Monica slopes. To remedy this information gap Mountains, or to the north in the Just prior to the fires and con- and to identify critical areas for plant Verdugo and/or San Gabriel Moun- tinuing to the present, a collection conservation, an informal, volun- tains. of neighborhood groups and the Los teer-based “Griffith Park Rare Plant I also searched for taxa known Angeles/Santa Monica Mountains Survey” was launched in spring 2010 in the area only from historical col- Chapter of CNPS funded several (Cooper 2010). The botanical his- lections (Consortium of California projects aimed at gathering baseline tory of an area can be a challenge to Herbaria 2011), though some of biological data on its plants and ani- uncover, even for trained research- these were likely collected in areas mals. These were carried out in con- ers. Most parts of California remain no longer undeveloped (e.g., the Los junction with the development of a very poorly known botanically, in- Angeles River and “Providence wildlife management plan funded cluding sites within urban areas. Of- Ranch,” since converted to Forest by the City of Los Angeles (Cooper ten there are a few local experts who Lawn Memorial Park). A small group and Mathewson 2009). While the have botanized in an area flora of the Santa Monica Moun- and have kept at least Figure 1. Locations of Rare Plants in tains as a whole has been well docu- some field notes (or to- Griffith Park mented (Wishner 1997; Gibson and day, digital photographs), Prigge 2003; California Native Plant and can help put together Society, undated), that of the far a list of species likely to eastern end of the range is compara- occur based on their ex- tively less well-known than the large, perience in the region. protected areas to the west such as Such observations may Topanga Canyon State Park and the be supplemented by plant Santa Monica Mountains National collections in local her- Recreation Area. baria, which are often the Aside from scattered references only record of species (e.g., McAuley 1985), the flora of long gone from urban Griffith Park had never been syn- sites such as native wild- thesized, although dozens of speci- flowers. mens had been collected here since Through my own the mid-1800s, mostly prior to 1950 fieldwork conducting (Consortium of California Herbaria wildlife surveys in the 2011). The one available checklist park since 2007, I was of the plants of the park (Brusha able to identify key habi- KEY: Green: Nevin’s barberry (presumed planted) 2003) does not differentiate between tat features most likely Magenta: Plummer’s mariposa lily (generalized planted and naturally occurring to hold rare or interest- locations; plant is very widespread) taxa, and presents just a fraction of ing plants, such as rock White: Catalina mariposa lily the true species diversity. Currently outcrops and remote Yellow: Slender mariposa lily an as-yet unpublished checklist of canyons. To begin the Dark Blue: Clay bindweed Light Orange: Humboldt lily the park’s flora stands at more than task of locating rare and Light Blue: Hubby’s phacelia 500 species vouchered or photo- significant species and Red: San Gabriel Mountains leather oak (pending graphed (Cooper, forthcoming). populations, a list of tar- further identification) This is nearly half the known flora get species was devel- of the Santa Monica Mountains and oped with the help of Richard of volunteers used this species list, includes 350 natives. Still, the park Fisher, Bart O’Brien, and Carl along with a map of the park has apparently never been a popu- Wishner, local botanists familiar (Cartifact, Inc. 2007) that had been lar place for botanizing, probably with the flora of the Santa Monica divided into 40 survey blocks, and
VOLUME 38:4/39:1, OCTOBER 2010/JANUARY 2011 FREMONTIA 19 Figure 2. Distribution of Rare and Locally Rare Plant Species in in the Los Angeles area if they per- Griffith Park, by Survey Block sist at all. Three species of mariposa lily occur in the park, and exhibit an interesting, non-overlapping pattern of occurrence, with Plummer’s mari- posa lily (Calochortus plummerae) by far the most common. Hundreds of these spectacular pink and yellow lilies were encountered on thin, grav- elly soil along ridges, often in asso- ciation with yucca (Hesperoyucca whipplei), giant stipa (Achnatherum coronatum), coast buckwheat (Erio- gonum fasciculatum), and chamise (Adenostoma fasciculatum). They were often found along small trails and footpaths (including equestrian routes), where this activity appeared to limit non-native grasses, among other plants, that might otherwise overtake the lilies. Catalina mariposa lily was found in pockets of grassland on moist, heavy clay soil near the south-cen- Outline of park is drawn in gray. This grid system follows that used by Cartifact, Inc. tral area of the park, with two large (2007) for a Griffith Park map, and notable natural and physical features are listed within each block. The colors correspond to the number of rare species found within each block, populations discovered that exceed as indicated by the key on the right. For example, pale pink blocks had two to three rare 100 plants. Finally, the slender mari- species, while the darkest red blocks had nine or more. posa lily (Calochortus clavatus var. gracilis) was discovered prior to the sent me photos and notes from their historical specimens (Table 1). (A start of the survey, in a single patch forays throughout spring 2010. description of the California Rare of fewer than 10 individual plants in Plant Ranks, formerly the CNPS a grassy opening in chaparral on a RARE SPECIES FINDINGS Lists, is available at http://www. remote peak near the center of the cnps.org/cnps/rareplants/ranking. park. No other populations of this From this effort, 13 rare species php.) Of the four species believed stunning yellow lily were encoun- (California Rare Plant Ranks 1, 2, extirpated from Griffith Park, only tered, despite much searching. and 4) were identified as occurring one, the Brewer’s redmaids (Calan- Humboldt lily (Lilium humboldtii or having occurred in or adjacent to drinia breweri), has been collected var. ocellatum) appears to be con- Griffith Park. Of these, nine were recently in the region near the park fined to just four oak-shaded can- found to be extant (still in exist- (Verdugo Mountains); the remain- yons in the park, with most plants ence), and four are known only from ing species are apparently very rare (50+ individuals) located in Brush
LEFT: Plummer’s mariposa lily is found frequently on steep ridges on eroding soil throughout Griffith Park, Los Angeles. All photographs 0GB63/CB6=@C<:3AA=B63@E7A3A>3174732 KMIDDLE6/>/@@/:>3/3;3@57<5/B=>/6C3<5/&3/9/4B3@ 47@37< @7447B6&/@9 KRIGHT: The rare Humboldt lily is found beneath oaks in several deep canyons in Griffith Park. Photograph by Gerry Hans.
20 FREMONTIA VOLUME 38:4/39:1, OCTOBER 2010/JANUARY 2011 TABLE 1. SPECIAL STATUS PLANTS AT GRIFFITH PARK
Representative Park status Species Legal status specimen1 (40 survey blocks)s)
Nevin’s barberry Federal: SBBG37272 Probably introducced; Berberis nevinii Endangered found in 5 surveyy State: blocks Endangered CA Rare Plant Rank 1B.1 Brewer’s redmaids CA Rare Plant JEPS17234 Historical Calandrinia breweri Rank 4.2 specimen(s); no modern recordd Catalina mariposa lily CA Rare Plant RSA15196 8 survey blocks; Calochortus catalinae Rank 4.2 (“Cahuenga Pass”) heavy clay soil slender mariposa lily CA Rare Plant (photograph 1 survey block, Calochortus clavatus Rank 1B.2 only) < 10 plants var. gracilis Plummer’s mariposa lily CA Rare Plant LA29033 13 survey blocks,, Calochortus plummerae Rank 1B.2 gravelly ridges Clay bindweed CA Rare Plant UCR216375 1 survey block, Convolvulus simulans Rank 1B.2 < 10 plants many-stemmed liveforever CA Rare Plant RSA397814 Historical Dudleya multicaulis Rank 1B.2 specimen(s); no modern record large-leaved filaree CA Rare Plant RSA390952 Historical Erodium macrophyllum Rank 4.2 (“Providencia specimen(s); no Ranch”) modern record southern California CA Rare Plant JEPS58691 Common park-wiide; black walnut Rank 4.2 not mapped Juglans californica Humboldt lily CA Rare Plant (photograph 6 survey blocks, Lilium humboldtii Rank 4.2 only) mesic canyons var. ocellatum Hubby’s phacelia CA Rare Plant UCR209589 2 survey blocks, Phacelia cicutaria var. hubbyi Rank 4.2 sedimentary rockk Cooper’s rein-orchid CA Rare Plant RSA382793 Historical Piperia cooperi Rank 4.2 (“Providencia Ranch”) specimen(s); no modern recordd San Gabriel Mountains CA Rare Plant RSA652868 1 survey block leather oak Rank 4.2 Quercus durata var. gabrielensis
1 Location is “Griffith Park” unless otherwise indicated. RSA = Rancho Santa Ana Botanic Garden Herbarium SBBG = Santa Barbara Botanic Garden LA = UCLA Herbarium JEPS = Jepson Herbarium, UC Berkeley UCR = UC Riverside Herbarium
Sources: Consortium of California Herbaria 2011; Cooper 2010.
VOLUME 38:4/39:1, OCTOBER 2010/JANUARY 2011 FREMONTIANTIA 21 Another difficult-to-assess rare flora, and more probably await dis- plant in the park is the San Gabriel covery. The only known popula- Mountains leather oak (Quercus tion of dwarf brodiaea (Brodiaea durata var. gabrielensis, California terrestris var. kernensis) in the east- Rare Plant Rank 4.2), which is ern Santa Monica Mountains (A. known from a single collection in Gibson, pers. comm.) was also dis- 1991. However, more study and col- covered by a volunteer during the lection of various scrub oaks in the survey. park are needed, particularly since Uncommon species reaching a Griffith Park may lie within an in- local distributional limit near the trogression zone between the flora park include erect goldenaster (He- Dwarf broadiaea, a locally rare plant other- wise unknown in the eastern Santa Monica of the Santa Monica and San Gabriel terotheca sessiliflora var. fastigiata), Mountains, was discovered just outside the Mountains. This variety appears to the latifolium subspecies of the wide- park boundary in 2010. be otherwise unknown in the Santa spread California fuchsia (Epilobium Monica Mountains. canum), and valley cholla (Cylindro- Canyon in the southwest corner. A map showing the distribution puntia californica var. parkeri). A few Hubby’s phacelia (Phacelia cicutaria of the above rare species in the park common wildflowers in the park var. hubbyi) was found on exposed, is provided in Figure 2 on page 20. show more of a San Gabriel Moun- eroding sedimentary deposits at the tains affinity, including Canterbury far southeast corner of the park, on LOCALLY RARE SPECIES bells (Phacelia minor), one of the soil probably deposited by the an- most abundant spring annuals in cient Los Angeles River that flows Several locally rare species were the park, becoming much more lo- nearby. Thousands of these plants found in substantial populations in calized farther west in the Santa bloom in early spring in the under- Griffith Park. Both Nevin’s brickle- Monica Mountains. story of open black walnut wood- bush (Brickellia nevinii) and Ft. The population of southern Cali- land. The tiny clay bindweed (Con- Tejon milk-aster (Stephanomeria fornia black walnut (Juglans califor- volvulus simulans) was found by a cichoriaceae) are frequent on rock nica) in the park is so large that it volunteer in 2010 on a moist, grassy outcrops and roadcuts throughout was not mapped during the survey. slope on heavy clay near the south- the park and even in surrounding Black walnuts form a continuous western border of the park just north residential areas to the south. East- woodland/high shrubland on sedi- of Hollywood, a site that also sup- wood’s manzanita (Arctostaphylos mentary soils in the southeastern ports the only park population of glandulosa ssp. mollis), chaparral pea corner of the park, and this is also a chocolate lily (Fritillaria biflora). (Pickeringia montana), and interior dominant species in the chaparral Nevin’s barberry (Berberis nevinii) live oak (Quercus wislizenii var. fru- that cloaks the northern slope of the is arguably the most famous rare plant tescens) occur high atop Cahuenga park. in the park, and also the most prob- and Burbank peaks within a dense lematic. Most stands (dozens of chamise-manzanita chaparral above PATTERNS OF DIVERSITY plants each) occur in two popula- the 1,600-foot elevation level, with tions. Scattered plants located since smaller numbers of manzanita and a Although areas at the lowest el- 2007 have all been along major roads single clump of interior live oak near evations at the perimeter of the park (strongly suggesting a horticultural Mt. Hollywood. tended to support fewer target spe- origin), or just down-slope of estab- “Moss gardens,” where soil has cies, several featured a handful of lished populations. Whether plants collected at seeps on rock faces, sup- locally rare species. Important popu- at Griffith Park originated from lo- port a variety of bryophytes, ferns, lations, including the only known cally-collected seed decades ago— and rare annuals at Royce Canyon local occurrences, were found at possibly from now-extirpated native and east along the north side of Mt. multiple and scattered locations, populations in the Los Angeles area— Bell, including California saxifrage making it difficult to declare a given it seems likely that the current popu- (Saxifraga californica), Peninsular area unimportant for any rare plant. lation is not naturally-occurring onion (Allium peninsulare), Fremont Not surprisingly, the fewest target (USFWS 2009). Still, Griffith Park is star-lily (Zigadenus fremontii), and species overall were found in the within the historical range of the spe- (Royce Canyon only) a white-flow- northeastern corner of the park. This cies and all plants occur in a low- ered form of Cleveland’s shooting- area that has probably seen the most elevation, arid chaparral community star (Dodecatheon clevelandii). A few intensive human-caused impacts with a species composition very simi- areas of private land adjacent to the over the years, including the con- lar to known natural occurrences. park were found to be rich in scarce struction of a large landfill in the
22 FREMONTIA VOLUME 38:4/39:1, OCTOBER 2010/JANUARY 2011 1950s, the installation of a vast net- the distribution of rare and local- Nevin’s barberry, one of the rarest plants work of metal irrigation pipe de- ized plants can be an important first in California (in the wild), thrives in signed for fire control (but never step in a site’s conservation. The in- Griffith Park, although the entire popula- tion is suspected to have been introduced functional), and widespread plant- volvement of local volunteers not decades ago. It is a large shrub found very ing of eucalyptus and pines, ostensi- only contributes information to this locally on loose, gravelly soils within bly for “beautification” starting in process, it helps ensure that the hu- chaparral, and is endemic to southern the early 1900s. man community will be invested in California. Photographs by Gerry Hans. It also became clear in our survey resource conservation in “Holly- that most scrub-covered slopes in the wood’s backyard.” park were largely devoid of rare plants, with diversity mainly confined REFERENCES to microhabitats such as seeps in deep canyons, sandy/gravelly ridges, moss Brusha, R.F., ed. 2003. Native and ex- gardens, rock outcrops, and patches otic flora of Griffith Park: Source: Bill of grassland on wet clay soils. Areas Eckert. Unpublished checklist. of the park that combined these fea- California Native Plant Society. 2010. Inventory of Rare and Endangered tures predictably supported both a Plants. Vols. 7–10. http://cnps.site. high diversity of rare species and large aplus.net/cgi-bin/inv/inventory.cgi/ populations of them. Home. The identification and documen- Cartifact, Inc. 2007. Griffith Park tation of these microhabitats are (map). City of Los Angeles, Office critical to making management de- of Councilman Tom LaBonge. cisions that benefit biodiversity, and Consortium of California Herbaria
VOLUME 38:4/39:1, OCTOBER 2010/JANUARY 2011 FREMONTIA 23 ABOVE: “Moss gardens,” or patches of moist soil within rock outcrops, are key areas for rare >:/
(CCH). 2011. Data provided by the McAuley, M. 1985. Wildflowers of the participants of the Consortium of Santa Monica Mountains. Canyon California Herbaria. http://ucjeps. Publishing, Canoga Park, CA. berkeley.edu/consortium/. National Park Service (no date). Plant Cooper, D.S. 2010. Griffith Park Rare checklist for the Santa Monica Plant Survey. October 10, 2010. Un- Mountains National Recreation Area. published report. http://www.friends http://www.nps.gov/samo/nature ofgriffithpark.org. science/plants.htm. Cooper, D.S. Forthcoming. Flora of United States Fish and Wildlife Service. Griffith Park. Annotated checklist. 2009. 5-year review for Berberis Cooper, D.S. and P. Mathewson. 2009. nevinii (Nevin’s barberry). Carlsbad Griffith Park wildlife management Fish and Wildlife Office. August 14, plan. Report submitted to the Los 2009. Angeles Department of Recreation Wishner, C. 1997. Flora of the Santa and Parks by Cooper Ecological Monica Mountains: Synonymised Monitoring, Inc. http://www.griffith checklist and index. Crossosoma parkwildlife.org. 23(1):1-52. Gibson, A. and B.A. Prigge. 2003. Re- vised flora of the Santa Monica Daniel S. Cooper, Cooper Ecological Moni- Mountains. Final Report. Herbar- toring, Inc., 255 Satinwood Avenue, Oak ium, University of California, Los Park, CA 91377, dan@cooperecological. Angeles. com
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