TreeoftheMonth,December2016:Japaneseumbrellapine,koyamaki(Sciadopitysverticillata)

JapaneseumbrellapineisanunusualconiferendemictosouthernJapan.FossilevidencefromtheCretaceousandTertiaryperiods(145to2.5millionyearsago)suggeststhatJapaneseumbrellapineswereoncecommonacrosstheNorthernHemisphere,buttodaySciadopitysverticillataistheonlysurvivingspeciesinthefamilySciadopityaceae.Sciadopitysneedlesareuniqueamongconifersbecausetheyaretechnically“doubleneedles”,twoleaveswithseparatevascularsystemsfusedtogetheralongagroove.Theneedlesaregroupedalongthebranchesinwhorlsof20-30,anarrangementthatresemblesthespokesofanumbrella,whichleadtothecommonname“umbrellapine”.Theneedlesare8-14cmlongandveryflexible.Sciadiopitysalsohastiny,brownscaleleavesthathugtheshootsbetweenthewhorlsofneedles.TheJapanesecommonname,koyamaki,referstoMountKoyaorKoyasan,atempletownsouthofOsaka.Koyasanisnestledinavalleysurroundedbyeightmountainpeaks,andistheheadquartersoftheShingonBuddhistSect.Koyamakiarecommonlyfoundinthearea,andmanyofthetemplesandshrineshavethetreesplantedontheirgrounds.Koyamakiistheimperialcrestforten-year-oldPrinceHisahitoofAkishino,thirdinlinefortheChrysanthemumThrone.Japaneseumbrellapineisaslow-growingtree,eventuallyreaching20-45meterstallinthewild,althoughincultivationitrarelygrowsmorethan10meters.Theneedlestendtoturnbronzy-yellowinwinterincold,sunnyclimates.AtVanDusen,umbrellapinecanbefoundgrowingalongtheshoresofHeronLake(seemaponreverse).