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Madrono, Vol. 60, No. 3, pp. 258-259, 2013 NOTEWORTHY COLLECTION CALIFORNIA eastern New South Wales, Australia. Cultivated widely in much of the temperate, subtropical, and tropical Sphaeropteriscooperi(Hook, exF. Muell.)R. M. world, the species exhibits considerable ecological Tryon (synonym Cyathea cooperi (Hook, ex F. Muell.) tolerance, being capable of survival in a variety of Domin (CYATHE—ACEAE) (Australian tree fern, conditions from periodic cold and freezing to extreme Cooper’s tree fern). Los Angeles Co., Santa Catalina heat - so long as ample water is available. The species Island, Twin Rocks, channel-sidecoastal bluff, uncom- haslongbeenusedornamentally, particularlyinHawaii mon but widespread along open, rocky cliff faces, and othertropical Pacificislands (Medeiros et al. 1992; characterized by exposed, granitic and sedimentary Wagner 1995). In North America, S. cooperi has been sandstone soils, and very littlemannual rainfall, widely cultivated and is commonly seen in managed 33°24'50"N, 118°22'26"W, elev. 218 (715 ft), 23 June landscapes throughout California and as far north as 2011, J. R- Clark1020 with T. Dvorak, C. delaRosa, S. BritishColombia, aswellasintheAmerican Southwest Ratay, and T. M. Summers(CATA, RSA, SBBG, UC). whereirrigationisregular, andintotheSoutheastasfar Collection notes. Associated species include Dudleya South as Florida and the Caribbean (Wood 2008). virens (Rose) Moran subsp. hassei (Rose) Moran, Significance. First report of the species being Mimulus aurantiacus Curtis var. parviflorus (Greene) naturalized in California. Thepotentialforinvasiveness RaDo.ntdhMr.R.hTuAhsosmitpnastn.edg,rioOffopluLinyatoin(aNoutltihtta.to)mrnaluBiessnf(tlhEo.nrgie&blumn.Hd)uosoCokAc..keGrf.erlaely,x bt(hMyeeSds.epeiccoriooepssereiistciasol.ntsh1io9du9eg2rh)etdatsaownbeoelxlhiioagushsoiwtnehteehrdetiwrneotpaliltcraoolfpiHrceasgwiaaonindis subsp. floribundus (the endemic Catalina ironwood) is including Mauritius and Madagascar. Moist subtropi- also present near the site, although no S. cooperi are cal andeventemperateareashavealsobeen invadedby immediatelyadjacentto this stand. Onlytwo otherfern S. cooperi including southern regions of Eastern and species were documented in the vicinity, a single Western Australia and, most recently documented, a individual of Woodwardiafimbriata Sm. growing in a restricted coastal region of the temperate rainforests damp seep along the south side of the bluff and of Oregon, USA (Wood 2008). The discovery of a scattered individuals ofPolypodium californicum Kaulf. naturalized population in southern California repre- growing mostly in shaded areas. sents the first-ever report ofthe species being natural- A general survey ofthe locality was undertaken and ized in a markedly dry, Mediterranean-type climate. at least 20 individuals of S. cooperi were observed Recent research in modeling natural and escaped growing in and among the cracks and hangs of the ranges for potentially invasive species suggests that bluffs. Some ofthese individuals were growing in areas native ranges and ecologies might under-predict the that were accumulating and storing water while others diversityofhabitats availableto a particular speciesfor appeared to be growing directly from the dry, barren invasion (Fitzpatrick et al. 2007; Pearman et al. 2007; rock faces. Aspect did not appear to have bearing on Rodder and Lodders 2009; Mandle et al. 2010). The plant establishment; all slopes ofthe formation had S. discovery ofa naturalized population ofS. cooperi on cooperi individuals growing on them. Species directly Catalina Island in an area of relatively high exposure associated with individual S. cooperi plants were few, and very little apparent moisture supports this prevail- and ofthese Mimulus aurantiacus was most commonly ing notion. However, habitats such as the California seen in physical proximity to the ferns. Channel Islands that at first appear unsuitable for wet- Individualplants of-S. cooperirangedinsizefromless lovingspecies suchas S. cooperishould bereconsidered than one meter in height, including fronds, to approx- in light ofphenomena such as a persistent marine layer imately 1.5 meters total height. The largest trunk and fog drip that can dramatically increase available observed measured approximately one meter tall with moisture (Fischer et al. 2009). These and other adiameterofapproximately 10-15 cm. Frondswere on environmental variables, if modeled, might accurately average one meter in length, although smaller on some reflect true invasible ranges for the species (Peterson individuals growing in particularly exposed areas. All and Nakazawa 2008; Mandle et al. 2010). plants that were physically accessible were observed to Within species variation and local adaptation must havefertilefrondsandwereactivelyreleasingsporesvia also be considered in explaining the apparent range sori near the distal ends of the fronds. Older, dead expansion for S. cooperi (Broennimann et al. 2007; frondsdidnot appearto bedehiscingfromthe trunk as Mandle et al. 2010; Wang and Guan 2011). Ferns in is thought common for the species (Medeiros et al. general are ecologically plastic and both the gameto- 1992); instead, on all observed specimens, trunks were phytic and sporophytic generations exhibit the propen- routinely covered in dead fronds. Age could not be sity to tolerate and adapt to harsh environments assessed,butpreviouslyunidentifiedphotographsofthe (Watkins et al. 2007), including thosecreated following naturalized tree ferns from 2007 were recently discov- disturbance and/or dispersal to new and different ered and reviewed in preparation for this paper environments (Page 2002; Saldana et al. 2007). Many (Catalina Island Conservancy private photograph col- ferns including S. cooperi exhibit high reproductive lection; images not shown). Based on this finding, the output via spores that are highly dispersible, factors population is at least 6 years old and most likely older, thatmightbecontributingtodispersalto, andincreased considering the size ofspecimens in the photographs. odds for, establishment in drier and presumably less- Previous knowledge. Sphaeropteris cooperi is a com- typical environments for the species (Durand and monlyplantedornamentaltreefernspeciesnativetothe Goldstein 2001; Page 2002; see also Lavergne and subtropical rainforest of eastern Queensland and Molofsky 2007). 2013] NOTEWORTHY COLLECTION 259 Regardless of cause, the potential for additional success of an invasive grass. Proceedings of the naturalized populations of S. cooperi along the Cali- National Academy of Sciences, USA 104:3883- fornia coast and other coastal Mediterranean environ- 3888. ments worldwide is expected. Research into modeling Mandle, L., D. L. Warren, M. H. Hoffmann, A. T. and identifying these expected ranges and localities is Peterson, J. Schmitt,andE. J. vonWettberg. therefore justified. On-the-ground surveys are also 2010. Conclusions about niche expansion in needed to locate and manage naturalized populations, introduced Impatiens walleriana populations de- if and where they exist. The novelty of this recent pend on method ofanalysis. PLoS ONE 5:e15297. discovery of naturalization and potential ecological doi:10.1371/journal.pone.0015297. range expansion warrants additional field observation Medeiros, A. C., L. L. Loope, T. Flynn, S. J. and studyaswellaspopulation genetics research. Asof Anderson, L. W. Cuddihy, and K. A. Wilson. this publication, the Catalina Island population of S. 1992. Notes onthe status ofan invasiveAustralian cooperiisbeingcloselymonitoredbut not eradicated to treefern(Cyatheacooperi)inHawaiianrainforests. facilitate current and future study. American Fern Journal 82:27-33. The authors wish to thank Alan Smith (UC) for PAGE, C. N 2002. Ecological strategies in fern confirmation ofspecimen identification and forhelpful evolution: a neopteridological overview. Review comments on an earlier version of the manuscript. ofPaleobotany and Palynology 119:1-33. Hank Oppenheimer, Plant Extinction Prevention Pro- Pearman, P. B., A. Guisan, O. Broennimann, and gram Coordinator, Maui and University of Hawaii at C. F. Randin. 2007. Niche dynamics in space and Manoa, isacknowledgedforinformativediscussionson time. TrendsinEcologyandEvolution23:149-158. the control and eradication ofS. cooperi in Hawaii. Peterson, A. T. and Y. Nakazawa. 2008. Environ- — mental data sets matter in ecological niche model- John R. Clark, National Tropical Botanical ing: an example with Solenopsis invicta and Garden (PTBG), 3530 Papalina Rd, Kalaheo, HI Solenopsisrichteri. Global Ecology and Biogeogra- 96741 and Rancho Santa Ana Botanic Garden (RSA), phy 17:135-144. 1500 North College Avenue, Claremont, CA 91711; Rodder, D. and S. Lodders. 2009. Niche shiftversus aP.nOd.TBoonxy27M3.9,SAuvmamleorns,,[email protected], nnaitcihveecaonnsderivnavtaissimv?e CrlaingmeasteocfhatrhaectMereidsittiecsrroafnetahne Literature Cited hooguysaengdecBkioog(eHoegmriadpahcyty1l8u:s67t4u—r6ci8c7u.s). Global Ecol- Broennimann, O., U. A. Treier, H Muller- Saldana, A., C. H. Lusk, W. L. GonzAles, and E. SchArer, W. Thuiller, A. T. Peterson, and Gianoli. 2007. Natural selection on ecophysiolog- A. GuiSAN. 2007. Evidence ofclimatic niche shift icaltraitsofafernspeciesinatemperaterainforest. during biological invasion. Ecology Letters Evolutionary Ecology 21:651-662. 10:701-709. Wagner, W. H., Jr. 1995. Evolution of Hawaiian Durand, L. Z. and G. Goldstein. 2001. Growth, ferns and fern allies in relation to their conserva- leafcharacteristics, and spore production in native tion status. Pacific Science 49:31-41. and invasive tree ferns in Hawaii. American Fern Wang, Z.-J. and K.-Y. Guan. 2011. High genetic Journal 91:25-35. diversityandlowgeneticdifferentiationintherelict Fischer, D. J.,C. J. Still,andA. P.Williams. 2009. tree fern Sphaeropteris brunoniana (Cyatheaceae) Significance of summer fog and overcast for revealed by amplified fragment length polymor- droughtstressandecologicalfunctioningofcoastal phism (AFLP). Botanical Studies 52:231 238. California endemic plant species. Journal of Watkins, J. E., Jr., M. C. Mack, T. R. Sinclair, Biogeography 36:783-799. and S. S. Mulkey. 2007. Ecological and evolu- Fitzpatrick, M., J. F. Weltzin, N. J. Sanders, and tionary consequences of desiccation tolerance in R. R. Dunn. 2007. Thebiogeographyofprediction tropical fern gametophytes. New Phytologist error: whydoestheintroducedrangeofthefireant 176:708-717. over-predict its native range? Global Ecology and Wood, W. 2008. Subtropical Australian Tree Fern, Biogeography 16:24—33. Sphaeropteris cooperi (Hook, ex F. Muell.) R.M. Lavergne, S. and J. Molofsky. 2007. Increased Tyron, found modestly established in Oregon. genetic variation and evolutionary potential drive American Fern Journal 98:113-115.