TIlt R<>I< 01 Fi", U'l Non...,.. Gm.mpoIa, Eooor>'<m<Ed'l<:d 'r_" w,", •••ll)."d A j,j",L<..

01983 SCOI'£ I'IIbh""'d by Joho ","~' ol s.-ltd.

CHAPTER 8

Concepts of Fire Effects on Plant Individualsand Species

J.S. ROWE

ABSTRACT

P1""ts >rC "",um.d '0 ad.pI '0 fi,. reg,m•. The '«:lift,""" io,.,...I••nJ .p.a'i.1p.all.,n, of fi .... in t/le bo,••110'.... plu, t/le ub"lunou...... of mos, ptan". r.r.<l<, i'unhl<.ly that 'POd•••,,'jJ••<!apl.tion, to burning 'egim« of pani,ular .ize-s, "minrs.aud int.n""e< can be J.,w,d, On 'h, othOT h.nd. i' i. r••",n.bl. to "pe<t theO"olution of broad. ""OTI.pping ."."gi., fo, coping "'ith fife. Planl' are g,ouped ••in".Je". ",.de".•,oider$.....".". and .ndute" ,n ord.t to •••mt ... pre.um.Jadapti'·. "oi" ....h ., ding from. d,".n« ed ""'.g. ,n ·b.n.....p,outing hompro'CC1ed ,,,.,,,,,, .•nd , n« to bu,n,ng,"The go"•• ar...IO'-..nt to foree.~tmg

.~n. Ii'·.n l<no,,'I.dg¢ of fir. beba"""" and te,....in.

S.l ISTII.OOUCTIOS

Thi' .hapter examines the eoologi.al role of fire in the adaplalions of plants.focusing primarily on the '·egemion of the tXlfcal forest region ,n NorthAmerica. Although the eoolog~ of northern Euro~an forests is simil.r. onl)p.ssing reference has been made 10 lhe literature of the Fen""""'ndianroun'ries, The chapter b<,gins w,th an exammation of some characteristics offires. and lhen the functional anal),i, of planl adaplation, 10 fire is di5Ctlsscd.Concluding sections deal wilh problem~ of idemif)·ing e,'olutionar)· response,10 en'ironmental forces and ,,·i,h the relc"ance of au,ecological informat'onin forecasting posl·fire ,ucce"'ioo, The botanical names in the texl and tablescan b<, found wilh lhcir .ulhorili.. in Moss (1959). H.le (1969). and Crum(1973).

S.l PATIERSS or FIRE IS SPACE ASD IN TIME

The large ,.gional pattern of fi,.. "aries with macr<>climatic regime ,,'hilelocally lhc pattern "aries with lerrain (landform,,·cgC1ation). Johnw" (1979)propo5ed lhat thc dimibulion of intenals belll'ccn fires, regionall~ ~mJ

'" The Role o[ Flu In .\o"he"" O~u"'p,,'o,Emsy.,,,,,,

locall~'. could be fincd b~ lh. W.,bull funclion Van Wavo, (1978a) .ho".dthaI tho age dimibution of fire-generated patches of fore'l Ic(>n~ljlliljng lhesame frcquenc)' disnibut;on as thc bet" een·fire imernl,) should in thcor}' hiIhe negat",'. uponemial function (whICh is one form of Ihe W.;bullfuonion). usummg random ;gn"ion, and equal probah'hnes of burnmg.".fl.....here. n ....pite Ihc unlikelihood of such simpl••'Sump';on, forcomplex terrarn, he demonstrated a reasonable fit to ..,'nal sel. of empiricaldata from nonhern forests.

A' a "'orking hypotlle5i•. the negatiw eXJXlnential distribution has anumber of appealing cbarael,n'lie<. A"umlng random fires at a ronstantrate. lh. r.'''procal of fire probability at an}" rlac~ equals lho fir~ cyd~ or fircmlalion period, "'hich is also lhe moan of tho agos of Ihe fir~·iniliated

palches, The fire c)clc can lh~rdare be: calculal~d "ilh case Iram Wnwn·lional 10r~SI in.'~nto~ dala, Common <'Slimates af firo cydcs far lh~ borealfarcsl arc 50 to \00 ~'ears (Kounz, 1967; Heinselman, 1973; Woods and Oa).19n, zackr;SS<ln, 19n; Van Wagncr. 197&1).Th~ negali"~ ~xponcmi,1 modd predicts lhal aboUlI"'"O-lhirds of a reglan

"'ill carry "ands lh,t art yaung.. th,n lhe fire C) cle and ahoUi ane-lhird "illcony slands that arc older than the fire cycle. ThuS" helerageneau. patchyfartit IS predicted a, lhe regiallal narm, ,,'ilh ..,m~ arcas rcburmng 31 >hortinlernls (because of ",ndam ignitian.) "hile alhers c>cape burning for longperiods,

The largeit percenlage af the annuall~' burned arca in northern fore,ts iskna"n la r~uh Iram a few large fir~ (Ra,,-e. 1979a). Haw" ... succcssiwfircs ne,'cr roincirn, in ar~a and this. plus Ih~ pr~,'al~n« of unburnedindusio"" ronfe ... on lh~ regional ,'egelatian lis multi·aged charaner.l.<l"",nt~n,it)'fir~s lhal do nat killlr~es go und~t~Cl~d in agt-<Iass anal}'5eS.bUlth~y add funh~r uriatian to tho ",alial m""'ic at lho und~rslO'~~ 1c\"~1.

Biomass accumulaTion is a fUncTion of lim~ since lasl fire. so fir~ jmensit)depends. 10 SOme extent. on fire frequency (Kilgore and Taylor. 1979;H~lnselman, 198\). The r~lalionship is nol Iin~ar be:cause fu~1 .".itabilil)docs nat parallcl biomass (Van Wagn~r. \979). Ho"·~'·er. if fir~-lO..fir~fr~qu~nri ... for a major r~gion such as Ih~ hor~al for"'l or its <ttllon, fit ,h~

negali"e e.ponenllal distribution. then in a general "'ay so should fireinlensili~s_ AI.." assumIng random ignilions lhe probabililies 01 fireref"U"cnr~ and inl~nsi" al an)' gi\"~n place ar~ fiu~d by a POIsson disrnbullon

(Van Wagner. 197!la) as exemplified in Table 8.1.II should be: nOled. howe,·er. lhal as a nalural selection filler, fire intensily

must "'" inlerpr~l~d by iii Imp..,IS on planlS ~eoording 10 'heir phenQlogies.Daubenmire (1968) dre,,' anemion to lhe greater sensili"ily 1o spring fires ofrool·season grasses (such as Paa pro'truis) rompare<:l "'ilh lhe later sproutingwarm·season grasses (such as Andropogon JCOpt1T;US). Phenological dif·ferences in Ihe horeal flora also eff.cti,·.I}" modif) lhe impact 01 fir. inl~n>it)"_

PI"n' lndi\'id""ls and Speci~s m

Table 8, 1 The probability lhol on; i,,-en place ~'Ilh", a reglOn will ..penenee S fi,e,durin, one lheoreheal fire ,yde 01 &:J year<_ a"""rd"'l to Ihe Po"",n d"lrihunonw'he,e i-I (.IOroge 'ge of "and equ.I, f f". "yd.) .nd P, _ • -I'N'_ Fue Inten,,';I' m• .,ured ,n kllow",,, rer metTe of fire fronl

,,,,

"

Probability

0.'

18,4

M.'

A"erage inter".1fire_l","fire

I)'ean)

"

ExpcC10dfud buildupflrN","fir.

.\lod<rat.

Fireinlen.ity"

Light,u,la.<fire'<.lOOk\,\, m- I

Surfaceorcro"'"fire.J((I...J~l\\ m-I

lnl'"><crownfire';>l5UIlkWm-'

"S<e M'Al1hu"nd 0><"")' 11960), Van" .~""r (197i:blCOOl"'''''"' ro Blu'-oecl, _ kW m x o,m

'He,,')'I.,1 ~"ild"pm'rre"'e'ode<lJI.1I from' "''''''' fire '"" rot ~m~h ro p''''t-fire -n<~

,"""h'

Furrhermore. Ihe aclual ,ele.", of energy", • fire pa..,,<. ",prcsscd askilowa1l< per mctre of fir< front (Van Wagoer. 1978b). m.y bear lillierelation 10 lhe 'urvi,-.I of perennating plant part. burled rn fll" ",il. TheImportanl parameter> are depth of burn in the duff and >oil femp<:ratureprofile. related 10 fire ..<idenee tJme (duration) or 'burnout time' (McArthurand Cheney. J%(,)_

Fire ",'-erity i' the al>Proprlate dcs.<:nptor of the degree of organic 'emo"aland of >oil heating. TIIU< on 'and) soils a fire of 10" inten<ity (low energ~

relea..) may ne,-erlheless be of high .."erity (all organic co"er remo\'ed andnear-surface ..ed,. rhiwme,. and roots killed). On the other hand. summerand autumn fire'_ when lhe duff I' dr). lend fo be more "'\'ere Ihan 'prrngfire' ""hen duff I. mor,1. and the effect< on the sun.'iyal and re,prouting ofpanicular ,pecie< can be qune different (Miller, 1977), Some of the mostInten.. fires recorded in lhe boreal foresl lIa"e had linle elfe'" on 'uhs.<:quentyegetation becau.. they occurred when the soil "'as \Iill wet or frozen In thespring (Kirl and Grigel. 1969).

The.. is a Slrong likelihood that fire c}'cles calculated for regions arecompo,ite< of "ariahle fire c~c1e< at the local 'ite leyel where terra;n isrelatl,-e1y uniform, Zackri'son (19n) rcportcd thaI dry lichen-heath 'ite<

u, Th~ Rol~ of Fiu ill So"h~T1l Ci~umpol/lr £cOJyslmu

burned three times as often a, moister blueb<rr)'-hNb 'ites, and he found thesame ratio of fire' in a compariwn of south·lacing and north·fac;ng moraineslo~s. Similar o~r...alions h.,-c been reponed b~ Row. and ScOller (1973)and by Tond. (1979). Thi. mean. that a lOO-year fire cycle for a large areamight comprise upland Clcl~ of 60 and 80 )urs on sandy and cia)' submate,plus lowland cycles of 120 and 14(1 years on bog borders and deep peal.,cspecti"dy_ The 'ok,ance 10 fir. trology of ecological land classificationsthat identify terrain unit' of combine<:! '-ogetation-Iandform al regional and,ubregionall.'-els is therdor. apparent (Rowe. 1979b).

The ,-oriable pattun. of boreal fires ,n space. time. and ,n,en\lt) a,.important. The) ca'l doubl on lhe ",isdom of searching for ,pecie,-"'ideseleclion pressures such as lOa)' r<:sul! in O1her regions and on olher oominemsfrom ronsislem prediclable paner", of shon-imervaJ lo",·inlen,il) fir•• , orlong-inlcrval high·imensil} fire" Thi' seem, panicularly perlinenl "here"'ide-ranging ,pecies-lhe majoril}' of lhe bOleal and 10'" arclic flora-areconcerned,

The serollny of Pmla ""n/alana. for example. ,ho".., a 'lali'tkal increasenonh""ard. (Schoenike el al.. 1959). bul ",en among the most serolinou,populalions a fe" open-cone indi"iduals le>lif} to lhe ,-anabillt}, of lheselection process, Young pines of most populations tend to Ix non·serolinous.•uggestin~ that seed slOrage in dosed Cone. i. ad'-amageous onl)'"hen slands arc dosed and mature. Referring 10 papers of Lotan (1976) andSchoenike (1976). Gill (1981) .uggested lhat lhe serolin)' of Pm", eonlorlfJ i'an adapMion 10 good sites, ",he~ hIgh productivity produces rapId fuelaccumulation and encourages fires of high inlensily, This implie, lhat in otherplaces "'here fires are fe",cr. and especially On 10""produeli"ily areas,seleCllon is for non·serotinous cones (SmIth, 1970) The Siles of non·serotinous pine described b} Lotan (1976) appear 10 aglU "'ilh lhehypothe,is.

Specific adaptalions of plams 10 fire. iflhey arc 10 be found. musl be al thelocal eeosySlem Ie"el '" here in the contexr of lhelf immediarc experiences lhefil arc separaled from the unfit.

8,3 LIFE-FORMS, ru~CTIO~S.Al"D FIRE

In order 10 relate planlS to Ihe fire en"ironmenr. lhose morphologic andr!e'-elopmemal tnilS adamageous for sur"i"al muS! fim be idenlified. Theron"entional IIfe·form classification (Raunkiaer. 1934) based mainl)' onposition of lhe perenn.ting organs reiatiH to the wil surface. is rele"aminsofar as localion of buds and seeds in lhe "ertical plane matches a gradIentof energy release during fire_ Ob,-iou.ly the hfe·forms ,,'ilh aerial perennatingplIns-lhe phaneroph)tes and chamaeph)'lcs--are mosl susceplible 10 des­truel;on by burning. "hile the surface and sub-surface l}'pes-lhe hemi-

Plant /ndindUilb Ilild Sp«iN 13'

cryploph}ln and cryploph}l~r~mo<.kralel} and ..~U prol«led M~n}

forbs (bfl»d·k~f berbs) ar~ cryploph\ln and, " AIMed b~ \OJI (1979), mooJO!;l,~. are hemlCrJPtopb~u·•. Thil. hclpl 10 explain the obocrnnon(D~ubcnmlle. 1968) lh~l f~'1,,~nl flln f..o". forbs o,er lu»nlbe.oph~t~....;'inl the unfa'ouD!>k IICllloOR in the seed ""'~relhead'>"Il11a~ at hem>cr)l"'lJIlI~'n Of 01 tr}p1oph}'C'i tkpen<hn, OIl ..hetbe,ltICi• .....-eli IIC at lbe: OIIrfacc Of .. itJun the totl

Rauntizf' bfe-fonM "'~,e ~gncd .....b lIC"en'} of re!J'Ol1a' e,",mne mmmd. and "lIb tbe: odc:a lb~, hf~·(orm spc-ctra ..ould ,,11ow reJlOflalrompan~s 01 cl,mal~ "Therefore lbe clllosorocal"'" ii not full} approprlalefor stlldl of firc·,ndl>Ced re.ponsn and adaplalion•. SpecirlC ceoloaocalprot>l~m. rcqu're aPl'roprial~ >1f11C1u,al·fIlIlC1l0n~1 mncep'. (Kn,ght andLoucks. 1%9).

Tabl. 8.2 D• ..,,,plo,, of lh. ·"i.n.ratio" ""'0" of plan' .peci •• (m",lIfi.d f,omN<>hl••nd Slat).,. 1971)

'Iodt of "'1"""'''''''' ."d rtprodue""" Ii'" ,·,..1Pl"OC~\,.,.,." ~.

\' - .bI. 10 rnpro<>l of bII""'" In lbe lunnik ......Yo "'""'" ank '0 rc>i>t~ ... 1M aoIul' ....,.. IlDd to co"ltn...."."'''011

IJO"'III &h« it Itbcu&II fi", trlb Ju'ODIIc>I

Dt>se,"",,,,,",~

o >f'CC'""I - .."b~ ~n.<'d poopapInSspean - ~«I j:. ....... <II doo "'"c~ - ~ ... tloe __

"c""""""' ,..,<__••••••_.~._ .... fI"I'<ft'

T.pean __Ii _ """ nubb>b~h .tie, " fir• .,.;I '*'po...... _nlltl> u..reafte. ""_I furth<, I""uotoa,_

R>pent> __... 'hal CItItIOl nI 1tnItIOd<at.1> ofl., fire bill ""'""'" unlil iDtDO ,tqu" ·n1 """ tIt.n ..... ('·1·_ lot >baoIt1

l'l'"'<ion - 'n.......nlS lba' can onll C>lallbsh 'DlJDCdU."\>· .flc, • fro.R.pod-po"·'h pioI>ctn.. ,lie> "''''' '" d,c ou, .."bou, ",'"n.n,d'''U'N"",,,

III Tim. Kol. '" ',,·"f.llif. hi'IO') ..·.n"-'hi.d \·".1 P,()f~

.\lo"u,.d f'''''' Urn•••ro (most ••",n, fi,.) .nd plo"od "'in~ 'hc f"llo~Inl

'~'mbols on a Ii..., "m. a;;,,'

p - prop>pJe••"". on l»I'''''d ",.m - reproducti,'c DU,un'~ ,•..,hod. product"", of P"OJ'l',ul..

~..I - ..... of >pttin ftoa:l """'mun,,} bl ........."'"• - _ of p""p"!ule> ftoa:l >lOUd _ftt> (DClt<: ••• for D

"POrial.

,., Th~ Rol~ of Fir~ III .\'onhun Cin:umpo{or E~OH.tmu

Au{~rok>glcal characters appropriate to the plant.fi" inteTaction h.,-cbeen pro~ b~' Lyon and S{icknc~' (1976). Noble and Slatye, (1977). andCat.Bino <I al. (1979). The la't \wo papers emph""ze three "'ital amibule,'that con'titute dimensions of the species 'regeneration nich., reproduction.com!",{,ti'm. and life cyde. The «heme shown in Table 8.2 was inspired b)'

the al"",. concepts although a number of libenies Ita'. been taken inredesign for Ihe subsequent discussion

Nmc lhat firsl place is gi"cn to method of regenCrat;on (Hgeta'i,',exten,ion) and reproduction. Although account is taken of compel;';" andsymbiotic interactions. these are under emph",ized relati'"' to their hea\'yemphasis in population biology lilcraturc. In a pulsed environment. charac­teristics sef\'ing invasion, ~d storage, and regro"'lh ta~e precedence o'"e'those sef\'ing competition. for imen;pecics reactions may not dc"elop before

Table 8.3 Mod< of "" .....tcoc. of plants ,n 'he con«,t of fire

DWm1lnul,·ba>,d, pro""ga'i"g primali/." til' d'.,pom

Inl,.de"

Jli~hl) d"""r>,,", Il""'••""~ fU~L"'e> "'ith ,Oon_l",.d di»<monule- (01<p<ci<s of Table 8.1),

C<I",t>don pu'p""'" X"Kio 'OIIen'"E"a<l<"Sp«ie• ...-ith r.lati".l~' lon~_li".d P"'l"'8ute. 'hilt ar. "ored in >011 or incanop) KI. 51. and ST ,pcci.,)

Porta ",,"'.". Rub,,,. ""8''''''Col)'dobs -"~I1'i" ...

A\'(,ide"

Shade_toleran' 'p«>e' that ,,"'" ly re,n"we burned are." la,. "'«:"""'nal,of«n "'i'li .~'mbiol" requirement> (OT and OR ,pecie,j,

Ab,,,, 1><I1<.""a Good",,,a ffp''''

11 V'~<I.".'e-fJ<,5d, p,opuS.""S p"martl" b" l!,m,OII'aland ,'<rueal ex"",lOn

Res",."Shade_,ntolerant ,p«"I....hose adult ,tag.. can ,um,. lou-",><"I> fire,(WI .pecie.).

Po"", """b,o"" E"<>pluH'wm ,..s",o'um

Endure"

R. 'prout,ng ..,..,.,.•~ade·,n'nl.ront or ,ol.ron,. U',~ .hallou 0'de.p bu".d per.nn.ling hud. (VI .nd VT .peei.,),

Pop"l", ",muloid" Almo crisp"

Plam Indind"als and Specie, '"anmher perturbatIon oeeurs. Grubb (1977) ha' argued persua,;\-dy thaI thcrearC Infinitc possibililie, for specics' coexistence on lhe ba'i' of differences In'regeneration niche'. prO\'ided that ecosystems ront;nue to pulse, Thuscompelition may often be a relati,,"ly unimponan' pan of rommuni'y nichestructure. particularly in se\cre nOrlhern ooreal en,ironmcnt',

8.~ FU~CTIO"iALADAI"TAT10:-;S OF PLANTS

The firsl lwl) -,-i'a1 atlribulc,' ronS1;luting a mode of persistence arcsummarized in fi"e categoric, in Table ~,3. A few example, of ooreal speciesin each categOTY arc given The lener descriptors relate specie, groups to the'regenerallon nicbe' outlined in Table 8,2. For the di",u"ion thaI follows.papers b~' LUlZ (1956). b~' Ahlgren and Ahlgren (I%i)). and by Ablgren(1974) pro'-ed particularly useful as <ource< of autecolog;cal informationL~'on and Slickn~y (1976) ha"e gi"en a useful1i't for the Rocky Mountains.Olher source, are acknowledged in the appropriate sections, Many ,pecieseannOI be specifically idenlified for one category nor i' there any impiicatlon'bal lhe) can be so identified in lhe future, An element of choicc. based onmy own experience ,n northern le'rain ... expre,sed in the selected example<,

These carl) arri"ers owe sueccs, 10 lhe copious produet;on of 'hortli\Cd",nd..Ji'<eminalcd propagules, The) lend to be shade-intolerant pioneering'fugili"es". dependably present though in "ariable quantity after fire regard·Ie'" of iI' eyde length and intensl1y Onec cSlabllshcd. lhe) usually 11"",.. andfruil profusei) or ,pread "egetali'·el,'. These arc good 'fire"'eeds"

Examples of in"ade" on dry or fre,hly burned ,iIC' arecCera/ooOlI purp"m<s Ow"m an',nuPoly"ichum pd,!u"m t"pilohiu", a"!,,,m!oli,,mArclagroslis lali!olia Pnp"f"s ''''''''foid''Benda papyri!ua (on the Pree"mbri~n ShIeld)Salix b'bbiana

On mOISt to wet burned ,iles in"aders are,F""arta hygromR/rica Calamagrnm< canadensisMarchantia polymorpha Ca"x amraAgro<ll< scabra Salix pla"i!olia

SeMclo cong"''''For spec,fie <deTenee 10 mcml\er< of th~se groups sec Skut,h (1929). $cotter(1964 and 1972). Crum (1973). Viereck (1973). Black (1977). V,cr-x< andOyrne" (1979). "nd An;hibold (1980).

Se\'eral special cases merit comment. The literature concerning t:pil()~iulI{

angus/ifol,,,m is ambiguous. but evidencc i' strong lhat. like Cal""'''!,r''''i<

U2

canadc,,,is. 11 is bolh an endu.ing 'proule. and an In.-adet h}' l«d. Parul".!relf"'!""'!" commonl} in"ades h} seed On lhe rock~ terrain of IhePrecamh.ian Sh,e1d bUI else" here ..,edllng. rarel) sur"ive and regeneralion i.by Hgelali,'e mean'.

An inlere..ing 'Uile of spc<"ies slore seed in lhe canopy. humus. Or mmeral""il. E"asion of high lemperature "ilh rapid ,ubsequent germinalion. i, thematCjI.". There are onl) a few boreal trees "ith seed banks in lhe canop):Pinus tumb/lma and P. amlmW wilh serolinous rones lhroughout thecro" ns, and Piera mariana wilh Icrminall} placed clumps of semi·scrollnouscones, Bolh respond to hIgh temperalure< "ith abundan' seed release.Allhough l'iera glauca relains small amount, of seed in ilS canop) for period,up 10 10 months after cone ripening. i' qualifies beller as an myadmgsemi·wk.anl'ree.

Pronounced dormanc) mechani'ms arc nece'sal)' for Ih",e seeds 'halaceumulate in lhe Stlil It i, I1kel}' ,hm some plant> in lh" calego" ha,e hardor refrae'or) seed'. triggered to germinale b} fire-induced high temperatures(Uggla. 1958, Cush" a rI al,. 1968, Vogl. 19U). Two kmds of 'bankers' can bedistingui,hed: shade·inloleram earl) successional ephemerals and semi.'okranl 10 shade-tolerant perennials lhat persi.. in ,uccessional rommunitleslong after fire,

The shon·li"ed ephemeral, are of'en annual o. bienniaL In habil ,hcyrcsemble 'he mud flal ruderal> described b) \an der Val. and Davis (l97iS)'hal lie m'er long periods belween brief posl-fire flowerings. During their'hon period, of abundance lhe) make ·one·,ho" seed deJlO'il' on ,he burnedsurface. "hieh subsequenll) ,,'ill form lhe base of lhe humu, la) er. As organichorizons are seldom romplctcl~' burned away (and as some ""cd mal workinll> lhe prOleClion of ,he uppc. mmc.al soil). 'he propagules of such planl,are f",ourabl> "luated for su" i' al e'en lhrough intense and "" ere fire,. Thehabit' of the"" and ,imilar species arc refcrred ll> b) Ahlgrcn (1960. 1979).Vier«'k (1~73). Ohmann and Grigal (1979). Example, are,

Cor."dal" umfHrl'lrms Aralia hispidoGuollium bicknellii Polygonum cilinod~

The semi·,ole,"nl and sh.de·tolerant 'pecies. pe'S1>ling in,o la,er succeS­'ional Sla&<,<. ronl.ibute 10 'he seed store for a much lon~cr period.Conse'!uenll) lheir 'banks" are less localized. Seed i' dislribuled lhrough lhehumus a, il accumulales and SOme m.) filler into lhe upper mineral soil(Moo.e and Weln. 1\177) M""tl> the .pccie, are t>crr).lruiled and lheaccumulaling seed store results from bird and mammal "ectOf<. Regenerationof such .pecic< IS I",oured b~ fires of 10" sc'enr~ and shorr duration lhat

Plmnllld"'id"ab and Sp,.,.i~. ,n

plants a, "'ell as

rCmO'C linle of the 'urface organic layer. Examples of semi-wlcram and,hade-toleram seed-banking species are:

Gm,.a,"o" h\-i"um Sym"hotlca,po. spp.Promus p~m)'I\'o"ica R'bes spp,Rub". S1rigosu. Vihurnum spr_Shepherdio ca"ade"s;" Com'" slolom!"a

These and similar species have been commented on by' Quick (1962). Marks(197J). ~loore and Wein (1977). and napin and Van CIc'e (1981)

Members of this th"d da" of disseminule-based plants arc farthesl from anydirect adaptations to fire. They a,e often listed in the Iitcra'ure as 'speciesoccupy'ing unburned areas'. meaning thal the) am\'e late ,n succession andprospe' "here fire q'des are long, As members of relali"ely' old andunperturbed communities they' tend to be mcsophy"e and tolerant. somerequiring prior modHical;on of the erosy'tem (by humus accumulation 0'leafy shade) before they' can in'ade by' propagules and malnra;n them'el""by "cgera""c mean,_

Examples of lUleram a"oiders areAbies balsa"'eu Unnaea borealisPicea glaaca Milello Iluda

Dcpendem a'-oideTh indude many saprophytic ,"<,cularshade-requ1flng mosses and lichens:

Circaeo alpma MOIlO/rapa "mporaCo'allorl,i~a spp_ Hylommium sple"densGoodyera re~n' Pdligero aphlllo,,'

Refe'ences '0 ,he,e and related ,pecies ha"e been gi,cn b" Ahlgren (1960).McLean (1969). Flinn and Wein (1977). and Zaekrisson (1981).

A,wwllobiu'" mnertean"", is the inteTestin~ ea,e of an intolerant obligaleseeder" ilhout fire·.-'ading or fire_enduring mechani'm', It, sur"i"al dcpendson fire a'·oidanee. lCt it para';ti,es the fire-dependent pine, Its refuge' are"er) dr) open site' "here iI' fruils arc nOt a!lacked by the fungusWallrotn"lla mceuthobi Ros. (Dowd,ng. 1929) and where erow'n fire' a,euncommon due to low forcst densi,y and sparse fuel a<:cumulalion. From suebfoci It ,pread, bet"'ccn fires to surrounding forcsts (Alexander andHawksw'onh. 1975), Parado,icaill. infcctcd tree, ore more ,usceptible 1ocrown fires lhan uninfected trees. because the para,ile cause, 'brooming' andthe retention of needle' (Dowding. 1929).

The abo"eground pan, of only a few intoleranl nonhern species Can

'" Th~ Role of Fire III S{",hem Circumpolar Ecosy'tm15

suc<essfully rem1 fire. Usually this abilit) is low' In Ju\cnile slage, butincreases with age. Examples arc:

PilluS ball!<Ji,,"o and P. coll/ortaEriophor~m '-ugmo"''''At maturity. the rcl",j\el~' 1hick bark of th~ pine p,<llCelS ag"in'l creeping

ground fires. while the lack of ladder fuel (due 10 ,elf-pruning and peripheralfoliage) redu"". the fr~'lu.ncyof "own fires. Pme i' 1he only boreal {,eo thaIsu",;ws repeated scarring. Pia" moriana. P. glaucu, and Larix laridllainfrequently live through .ingle fife, but rarely do Ihe~' double scar andsu,';ivc. Mature Etwphorum ,'ogi"mum resist' fir. b}' it' don,. tussock lorm(Wein and Bli". 1973).

Tall shruM ,uch as AI",... utip" and dwarf .hrubs such as Voce;ni"", spp,are occa,ionally' pruned by low-inten,ily fire' withoUl lotal killing of branchlissue, Howe'-er, the accumulalion of leaws under frutic"'" plant' u,uallyassure, sufficient fire inten,ity to kill the cambIum at the ground surfaooe, lhuskilling all higher pan, as well. Consequently shrubs are sprouting endurersrather than re'isters of fire.

8.4.5 Endure..

Plants able to "'prout afler the pa,sage of fire rompri,e a large and di\'erxgroup of phoeni" specie', As ju'-eniles or adult' they regenerate from stemba,es. rnizome'. root crowns, roolS, and other bclowground organs. Such·V·spc<:ies' include man)' of the hemicr) ptoph) tes and cryptoph) tes that in thenorthern forests and tundra make up two-third, to three-quaners of tne flora(Whillaker. 1975: ~)_ Their importance has led some to conclude that there islillie succession of the ,pecies-replacemen, type in certain boreal forests sinooe .w-"h a few notable e>ceptions among the Iree, and the cryptogam'. thepo't·fire vegetation simply sproulS from Ihe pre-fire 'tock (Smith and Sparhng.1966: Black and Bliss. 1978), The endurers 'hould not be confused withtolerant 'proutlng 'avoiders' that maintain themselws \'egetati\'el) in latesuccessional communities as long as fire docs nOt ,-isit lhem.

Survi'al of sprouting spc<:ies in the fire en\'ironment depends greatt)' On'-enical p""itioning of the perennating pans in the insulating humus andmineral wi!. A 'tud)' by McLean (1969) showed that the proliferation of atleast some leguminous species aher fire i' due to their deep. w-e11 prolCctedperennating bud,. Ho"'e"er. there are difficulties in categoriling ,pecic, as todepth of sprouting buds e.eept in a site-speciflc way', For example, VucCltlluml'itis_idMU nas been described as ha"ing shallow subterranean runners inSweden (Uggla. 1958). as rooting in the mos, layer in Ala,ka (Chapin andVan Oeve. 199 I). and as deep-rooted in northern Manitoba (Ritchie. 1959)_It is '-ery susceptIble to destruction by fire according to the firsl1"'-0 repom.but resistant and enduring according to tne third.

Pia'" Jndil'iduu/, find Sf"CiN '"In addition to the ecotl"pic and phenotypic dIfference' that can be expected

in "ide-ranging species. the positioning of underground buds i' alsoinnuen~d by the thickness of the humu, layer. As forest' and shrubland'increase in biomass, the rooting .y'tem, of constituent plant' tend to migrateup"ard, into the thickening duff l.y.., (Siren. t955). The probable reason i,that the ZOne of m"",mum biological acti,';ty and nutrient release alsomlgr..e, up"ards during succession (Viereck. Chapter 1!- ,h" ,'olume).Specie, initiall~' rooted in mInerai soIl may. if they su"i'e into the matUrercommun"y. be rooted In the n or F humu, laye.. where theirsucceptibllity tofire damage in dry years i' greatly increa"'d, From Ihi, Ihere foU",," theinteresting implication. supp<JrIed by obset\'atlons of fire dfect' in oldforest', that dup burnIng long-in.." al fire' ma~' "irtu.II~' elimin.te sprOUlingspecies "hile clearing the ground for in"ading species. On shoner fire ncle'with 10" fuel bUIldup .nd fire Inlen,,1Ie,. ,pecic, tend to ,tay rooted inmineral wil "here they ,u",,'e and contribute to the early stages ofrecolonization after fire (Flinn and Wein. 19n: Ch.pin and Van Cine.1981),

Example, of early ,uccessional 'hade-intulerant 'proutc" are:Pop"lus l'fm"loidr. ArClos/apl,yloJ uI'a-u"';AptXynum andrOJaemifolillm Ma;anlhrm"m canadensr

ArclOnaph)'loJ U"a_U"/ i' ,"riable; listed b}' some as • 'prouter (Seaner.1972) but by others as incapable of ,'egetati'e reproduction from under­ground part, (Lutz. 1956) (>r as ,uSl'eptiblc to fire because its 'fibrou, roo1>and stolons" are in the humu' (McLean. 1969). In northern S..katehewan thespeci.. 'prouts strongly from golfban·,izcd ba..1 burls (lignotubers) in themin"al soil (personal obse" ..ion) Furthe" i1\ name ,ugg"" an animal"eclOr. implying the likelihood that it is a seed-banking .peci.. (SI), Uggla(1958) reported that its thick-shelled seed' sU"'i'e fire in the upper "'il andare SlImulate<J to germinatiQn bY'the moment.,), hIgh temperatur.. of passingfir...

Examples of senti-tolerant to ,hade-tolerant late ,u,ce'S1onal sprou..I'; arc;1'01"'<1 crispa EqlliuIlIm ,-"I"alicumAralia nudico,dis I"rridi",n aquilinu",Cornus canadmJis

The la\1 group. and othe.. like them (see Ahlgren. 1960, McLean. 1969:Heinselm.n. 1973. Be..leigh .nd Yarranton. 1974: Archioold. 1979. andViereck and Dyrness. 1979). comprise a group of 'superspeeies' whosepre"alence .tlest, to their adapt.bll"y'. Able both 10 endure burning and tomaintain them..I,",;, under. canop}. they ep"omize Success allllO'Sl regard_less of fire cycle length. no"'e"er. their mesoph)tlsm confin.. them toen"lt<)nmen1\ with relati"el\ longer fire cycles than those of lhe intolerant'prouters

Ericaceou, chamaeph)"te,. and d"'arf shrubs ",'ith similar hahits such .s

\-<,~ lon~

rtfe ~d<

A'-oilk"DR'l"'ei«

Good'H" rep''''

CiTe".... ulp,,,,,

I/,-I,,.w"'''''''pl",d,m

P,I"~,,,,

"ph'h"",

A'Older>DT '1""''''

Ab'",bah"m""

Piuo ~I"",o

'<Ii,,/la ""da

AI"", ui,p"

A."lia ""Ji,a"li,

(""",",,a"ad,,,,i,

Eq""'''''''",hall,,,m

l'I"id,,,,,,aquili",,,,,

P"'""ich"",pillf~"''''

Ep,lobm'"a"g","!"'i","

CuI"mag'OJ'"

"""lid"""

Sltor,. w<rm<d"I<.or long fiT< ~-,k

Co",a"d."Ii,-ida

P,,,,,,,,""""'1"0,,1<4

Pi"",h.",.\5,,,,,a

[,topho,,,m,ag,,,a',,m

E'-aoJt"Cl 'J>Ccic'

Pi"",Ixm",i"""

I',eta "'a",,,,,,

[n'ermed..'efiTO ~"I<

E,-,de",ST and SI '1"";"

'"~,mp"'''

G"a"I"",lIic""tllii

M,,/ia h"p,da

Ap<><y""m""d_,,''''i!''','''''

ATt""'"pl,,1m",-a·",."

.IIaianJlI~",,,m

,,,,,ad~",,

Pop"l",1r~,""IQjih,

~'";,,ur< ~radien'

Bt"i1" glandulo.o .nd Empe""m "'g,um. abo qualify as specie, "h"'" main"'''agem IS 'egeta"'e ,egeneralloa, The rari,y of bu'ied ,·i"blc ~ed,

""",i'led "·,lh lhe~ 'peeies in Ihe SOUlhe,n fore>lS and in lhe subamie h",..~en reponed by Moore .nd ""'ein (19n) and hy Johnsoa (1975), Vacciniummyrlilloidrs, v. ,'i'i,·idata. V, uligillmum. Ltd,,,,, p"I'I$1'~' and L. gT(}fIl­I"ndi",m arc examples of cncads thai ,hn'c a. 'esprouteT'S in 'he frequenllyburned fOTOSI eros~',,<m, of 'be soutbern bQreal and Ihe subarctic.

8.5 sucn:sslO'>"A Sugo;esl,on a, 10 ho" lhe sp,,,''- groups a,e ad.pt<d '0 fire c)des ofdifferent lenglhs is 'ho\Cn in Table 8,~_ F,equent fires (,hml "'de) fa\"Our,p,outing shade-intolerant specic, and lh"'" ephcmerals lhat ban~ seed althe

Pi

mineral soil surface. A fire cyde of intermediale lenglh allows specics th~l ~re

re,i,lanl ,n the adull stage lO mature and ,u",,,'e. along ",uh lhO'Se lhat bank'eed' in lhe canopy or in lhe humus laj'cr. Prospering unde' shon.intcrmediare. or long fire cydes are the pioneering in"aders and lhe,hade·lolerant sprouung ·wperspecies·. With long fire 'l'de,. lhedi>seminule-ba'ed tolerant and sj'mbiotic ,pecies de-elop in 'dimax'commun"'e,

Note lhal increa,ing fire cyde Ienglh. from the !ell 'ide of Table 8,4 to lherighl. matches an apparcnt moislure gradient, as might be e.pected. Thusshon fire 9'c1e plant' tend 10 be >croph)'te,. while long fire cycle plams lend10 be mesophytes. Anderson and Baile}' (1%0) reporrcd thai a""ual hurn\ngin lhe aspen parkland of Albena increases xerophilic species.

The rele,,"nce of lhe adaplar;ons generalized in Tables 8,2, 8,3, and 8,4 10prediction of succe,sion i, ob"ious, g,,'en know ledge of fire cycle lenglhs. Onlhi' pallOrn, papers by Lyon and Slickney (1976) and b) Canelino el al.(1979) ha"e explored lhe possibililie, of modelling lhe multiple pathwaY"' of,ucce>sion in weslern North Amencan fore'''-

Beyond recognilion that post-fire species-site interactions arc complex(Shafi and Yarranlon. 1973). the fact lhal, in principle. ,ucce"ion can ne'erbe successfully predicted and modelled on 'he basi' of aUlecologicalinformalion alone needs emphasi" The populalions and communities in"h,ch man " inlerestcd arc only components of eC"')'Slems. and the processof succession expresses adjuSlmentS between all lhe c"mponents, fore,"mple, animal depredation of seed and orher propagules IS oflen a crniealfa<1or. Questions as to whelher succession is endogenous or exogenous(Bormann and L,kens. 1979; While. 1979) are strictly academic. SuccessionmuSI be more lhan an aUlOgenic process, for ecosystems are not closed, Eachlract of the earlh's surfacc is an open geographic system. exchanging energ>and materials (including dissem,nules) with its neighbours. In 'hon, eachland",ap<: c<:<>S)'Stem ha' an ecology that comprises the "'eb 01 relalionsh,pwilh lh. eco'yslems lhal ,urround 01. as well as an mle,"al ph}'siology, Toundemand and predicllh. behniour of organism, on any area O.e .. III anyceO'Sy'lem) lherefore rcquires all.nt;on to lheir broader environmentalmatrix. which is mosl easily conccptualized and identified as t."ain,

The problem of predicling .'egetallon succession i, sharply focused ,n thoseinSlances wncrc commUnil)' composition follo... ing fire is deri"ed aimOSIcomplelely from lhc sland's environment. Suppose Ihal a ,'cry old forest,from which intoleranl species ha,c disappeared, finally burns after a dry',ummer. The lhick humus layer is consumed do"'n to mineral soil. deslroy,ngmOst ollhe 'Iored seed populalion and tho", persistcnt resprouling ,pecic,...hose percnnating buds ha"e moved upwards inlO lhe orgamc la}'er. Theearl)' success,onal communi,y will then comprise invading 'peeie., Thelikelihood of their arTi"a!' in ""hal proportions and abundance, can only be

The Role of Fire in Sonhun Cin:~mpol~' Eco.yslmu

assc:ssed from prior knowledge of lhe surrounding lerrain (landforms, soils,biota) and climatic regime (winds. sn"w cOler. moisture regime).

It follows thai predkli"e modds of organism succession ha"e 10 find waY"of linking lhe components (plant'. animals) "Ilh lhelr 'palial mamx. Thisbringing togerher of twO Ie"els of organization can t>c accompli.hed throughlhe chorologk ('patial) appredalion of lerraln and its bioric relationships ase,pre.sed in maps. If praclical ecological pur~, are 10 I)., ,en·ed. lheconcenualion On specie~. popUI"lions. and communities a. 'things in them­"'I"e' (rather lhan a. ecosy'tem component' In an eoosy,tem malrix) muStI)., a"oided.

8.6 OlSCL'SSIO:-

Analyse~ of plant response, 10 en"ironmental force. can lake many route,.POpulalion blolog"IS. for e.ample. ha,e propo",d h)'polho,e. concerninge,'olulionary suategie. based on non-<ompeliti"e and compeliti"c (r and K)relalionships (Pianka. 1970). or on interaction< I).,lween compelit"eness."ress lolerance. and un,pedfied em'ironment.] disturbance (Grime. 1977).The difficulty in to'ting and making sense of such 'ysrems reflects theproblems of relating functionally labile individual. and populalions to oneanolher along continua "hose lWo- or lhree-dimenslonal axes ~annot t>crigorousl)' defined. On the olher hand. less theorelical ecological approaches",n'e .peeific purposes. For example. Vogi (1~74) has sugge'tod lhatgrassland ,pedes under lhe influencc of fire I)., under;tood not as occupantsof successional Slages bUl ,imply a, increasers, decrcasers. neutrals. invaders.Or rClrealers. rcflecting responses .imilar to lhose from grazing pre,sure(Stoddart eT 0/ .. 1975). Such praclical scheme. po.ition specie, securd)'relati"e to each other on particular liles, bur rhey do nUl address quesrions ofadaptalion, The artompl in Ihis chapler 10 ke; adapt,,'e trait. (plant­morphogenelic characrers of known cmlogic.1 importance) 10 a specificcn'ironmental force (fire) is perhaps a useful mIddle ground.

Harper (1977) has poinled OUI the difficulties of rolaling eeological(proximato) and ,,'olutionory (uhimale) dfects. 'Adaplation is alwa;,relrospecti"e." he .ays (p, 776). Wi", after the evolulion.ry facl. we examinerhe ecological relation,hips of today's sun i' 0" and projecl lhem into lhe pasras success s"alagem,. The philowphical difficuhy is lhe ease wHh whichecological cvidence can I)., adduced to suppon theory. ,,'hen histor\ has,wallowed up rhe ~ircumstance. of e'olulion. Conjeclure musr thereforeconSlitute a large parr of the reasoning about plant adaplallons 10 fire. andaboul fire cffo~ts on plants.

The problem is lhal the influence of fire on plants ,annUl t>c sharpl\' set olffrom lhal of orher agilatlon,. Morphologic characters that appear to haveI).,en selected for ,un';"al in rhe fire en,'ironmonl may be amibu'ed equally

,.,well to biotic or to cllmaric·soil ,tre,..,s. Also. presumed adaplalions ma~' ~

fonuilOus. The high roncentrat;ons of .'olmile substance' In lea' e< and ''''iss.amibulcd b~ some In ,,,IN:,;on pr.ssur. of herbi.'o,)' (Chapin and Van Cleve.1981) or 10 .~'mpyfosi, (Mutch. 1970). rna}' r.fle<:l the metabolic necessit;e, ofplam, in nu,nom.poor cn,-ironment'. where assimilate'S arc 'hunled ""0h}'drlXa'OOn. ralher than imo carbohydrate< and pro,.,ns (Forrest. 1971),

Furthermore. such adap'aliDn< as do ser\'. ,pecie, ,u"i"al under fireregimes ma~' represent preadapt.tions, d."eloped under rhe Influence ofearli.. and different select;'. forces, II is e'nlC<.'i"abk. for example. thal1hegrowth habn of gT3S>C~ and S<'dge~_ characterized b}' high rool .hoot biorn."ratios (Wein and Bli.. , 1973: Clark. 1977). is primarily' an adaptation to theneed for efficiem rcC)'chng of nutrients in a d'l' en, ironment and ",rondarily'" the effeCls of top 'grazing' by fire and by animal',

Such ca"ears ha,-ing been ~talCd, and they are repealed in ""'eraloutstanding re,-iew papers On plan,s, fire, and emlurion (Gill. ]981; Keele"(981). 'here can. howe"cr. be linle doubt that fire in en.'ironment> such asthe boreal forest has b«n and continu"" to be a potem ecologIcal andcvolulionary foree, On ,h,s as.umplion. the compara,i"e length, of fire eyel ...and of organi,m life C)'des a..ume significance,

Planrs whose life cyde, are long relative to fire-free episodes must,u<:eessfully meet th. full range of en"ironmental ,ieissitude•. induding fire,The optimum compromi", may be phenoty'pie plasticity (Bralkhaw, 1965)'hat firs 'hc species !O sUl'-i.-a] both of fire and of the en~uing successionalstag... of the encompassing eCO'y,tem_ Species w-"h relatively shon life cyclesfac<: different problems, If they reproduce >exually between fire" ",Ieeli,.pressures may' render them anfi' for fire sal',;,-.I Or for an)' early' post-fire"ersus a IalC post-fire role, The solution is e"her '0 adopl lhe fugili"pIoneering Slfatagem or to -reS! o"er' the imer-firc episodes as dormant seed,or bulk. in effect lengthenIng lhe life C)'cle relal;'e !O the fire g.'de in theimerests of maintaining generic integrity.

The fire pulse can either aCt directly on organism.-" hen presumably ,heyare selected for rcsislance to flame. heat, and smoke--or indir'<11)', "herethe post-fire en"ironment with i,S panicular physical and chemical compo.nems eliminates the unfit. From one "Iewpoml. fire is the predator seekingout and consuming plants as its energy source. "hlle lhey' enher a'-oid it in thesanctuary' of 'escape terrain' or respond on their home ground by erectingdefences and safel)' ",qu",,.ring the" viable reSOarces, From anotherviewpoint. cenain plants can be considered ae',,'e searchers after fire.tracking do"'n and scavenging burned","er ground "henn.. it appears.m,wing quickly and efficiently' to profit from ne"l)' ayailable reSOUrcesCompared "'Ilh the ·slay·at·homes' lhese are lhe fugiti.-... the act"ep~'rophiJe, "hose num\>trs ri", and fall ,,';th the fire c~'c1e like the I)n_<populalion tracking the UP'! and do"n, of the snowshoe hare. Of course. the

''''slralagems of su"';,-al~' escapmg fire. by' ropmg wilh n. Or b~' pun;uing it arenot mulually exclUSIve. for all may be practised to some extent by ;odi,-ida"l,and populations in lhe cou~ of Iheir life cycles.

8.7 CO:-;CLUS10:--S

A ",arch of the lil.rature show. a '-c'y large number of anieles reponing in"anOU' wa)~ and with ,.riable ,nSlght 00" species bch.\,c when subJl:ctcd 10periodic fires. The ,igoifican"" of fi,e as an emlutiona.} force rema,nspractically unknown. The difficulties of gaining a bener understanding offire-plam relationships CCntre <)n the following points which need 10 be takeninto accoum in pursuIng the fascinating stud) of .e'poo..... and adaptation"

(1) Fire is ooe of man) periodic perturb.,;on, in ceolngi,.l 'y"cms. Us"a,;ous effects. direct and indirect. interact ,,'ith oth~r 'trong ",I~ct;'·e

forces in the en,·ironm~nt. Fir~ is no!. for .,ampl~. the onl) ·prun~" ofplant a~nal part,. nor th~ onl)' d~stro~'~' of perennating organs in the,urfac~ humu, la),,-

(2) Assuming as • tentat;'e h}'l,oth.si. that the panem' of fir.. ow, I.rg.n"rthcrn '~gion, and ,n th~ cont~'t of ~\'olullonary lim~ ar~ a random",ric,. then the "'arch for plant ,peei~, adaptation. to particular 'izes.timing•. and intensities of burning ma~' not be realistic. especially forUl>lqUltou, ,peci~s.

(3) WIthin larg~ r~glon•. fir~, undoubtedl) occur more fr~qucn,l) on Wme'crr.in type' than on others, ,\t this local s;te 100'e1. particularl) "here,hort fir~ Clcle, arc the norm. ~cOl)'pic adaptatIon, can ~ ..peet~d

(~) The "'arch for adaptation, to fjr~ 'hould utiliz~ structural-functionalcritcria. such as lhos<:: life-form characteristies that bear on the abilit~ of,pecics to persist and r~g~ncral~ b) the '1fatag~m. of Invasion. e,·a,;on.a\'oidancc. r~,istancc. and cndurance.

(5) Phenot~·p;c pl'S1icit~ of perennial species complicate, the cat.gorizationof plantS., single \1ructural_functionallypes. SpeCI~S fr~qucntl) displa)two or mor~ '''atagem' bet"'ccn perturbation,. Also. morphologic andphy.iologi, ,hange. arc u,ual as plants age. pani,ularl) if the) arclong-Ii,~d perennial,. In short. compl";l) ra'her than simplicity shouldbe e'pect~d in lh~ adaptation. of organi,m, to pul,ing eN»)'lem'.

(6) Gi"en the function.1 role of organ i,m, in ~co'~'stems. it i' unr~aliSlic toallempt ~.,planallon, of poll_fire ,uCCeSSlon solely by reference 10 lneaut.colog) of pl.nt ,pecies.

11.11 ACKl'iOWLEI>GDIE",TS

It is a pleasure 1o acknowledge slimulating corresponden,. tnat induded

lSI

man; h~lpful rderence' and critical comment, from H.G Anderson. S.F.A'llo. O,W. Ar<hioold. A.W Baile;. D.E. DubC. C.T D;''lle... G,R.Fahnestock. J F. Franklin. M A. Hemstrom. A,H. Johnson. E,V. Komarek.R,E. Martin. P.J. Murphy. R,E. Redmann. R.W, V,'ein. P.lI-·!, Woodard. andP. Zager. Additionally. lI-I.E, Ale,ander and P.F. Stkkn~y proffered man;pertinent suggestions and the author is pankularl;' ind~bted to them

8.9 REFERENCES

Ahlgren. CE, (l960) Some effect> of fi,e on reproduc'ion .nd V",,·th ohege"'00n innortheastern ~1Lnt'>e..,... Ecology, ~t. 339--145.

Ahlgren. C.E. (197-1) Effe<:t. of fire' on tempErate lor",": ;-':onh eent,.1 Un,t«lSla'e, In TT. Kozl""',ki .nd CE, Ahlgren (<<I,). Fire ""d £ro.<)'Sle_,Academic Pte». Ne'" York. pp. 19:5-113,

Ahlgren, CE (1m) Emergen' ..edhnllS /tom soil on bu,ned and unburned red pine10test. Minn"Q'" for. R... ,\'ores No. 273, eolle~e of Fore"r)'. Sl P.ul.MInne..,ta. ~ pp,

Ahlgren. I. F, .•nd Ahlgren. C E. (1960) Erolo~ic.1 cffoc" of fore" fil«. BOI, R"l~. -183-533.

Alexander. ~I .E...nd Il.",ks...or,h. F.G. (1975) Wildl.nd fire' .nd d""arf mistlet"""A li'e1Otme re"iewof .",Iog)· and prescribed burning. US for, Sm'., Gen. r"hR,p. RM·jJ, II pp,

Ande""n. H,G, .nd Bailer. A W 09llO) Effects of.nnu.1 burnLn~ on ll-l_land ,nthe "pen parkland 01 e.st centr.1 Albert•• Can, J. BOI .. SII. 985-'1%

Ar<hibold. 0 W. (197<)) Buried 'i,ble prOj>Ogule' "" • f.etor ,n post.fir. tegen.r>tionin ""nhern S.,katche"'·.n. Can J. Bot" S7. -S4--58.

Archibold. O,W, (1980) Seed ,npu! ,nl0 • post-fi'e for..! "te In north.,nSa'katche"'an. Can. J. fo', Ru.. 10. 12'>-13--l.

B• .,le,gh. w.J. and y.".nton. G.A. (1974) Erolo~".1 .na1e~; .nd tactoes ofEquiul"m 'yl>'ari<u," durmg • I""'.fi,e ,u=,,",on. Can, J. Bot" 52, 2!99-1318,

Black. R.A, (1977). ReproduC1i"e l>iolo~r of P,«a mariana (~toU,) BSP., neeline.PhO lll..i,. Oep Bo,.ny. Unl"."i')· of Alben •. Edmonton. Albert., 170 pp,

Btao:;k. R.A...nd Bti". l.C. (1978) Rero,.ry ""Guen," of f'iJ;ea ,"a,iana·Vaceini"m"['gmos"," fore'" .fte, burnml near Inu"ik. ~orthwest Terri'ori... Can.d•.Can. J. BOI.. 56. 2OM--20JQ

Borm.nn. F.II...nd liken•. G.E. (1m) Cat"'trophic distmbance .nd thc "03d)>l.te in """hem h.,d...·ood forem. Am. Sc;.. 67, 661}-{)69

Brad,h3"'·. A O. (l'!65) holulion,,)' 'ign;ficancc of plieno'ypic pl.,t;c;'r in plants.Ad". Gener., 13. 1l5-1~5,

ea"olLno. P.J .. ;-':oble. I R. Sla,)'''' R 0 .. and Ke,..11. S.R. (1979) PrediC1inl themultiple p.th"·,y, of plant ,,,,,ce,,ion. Em'iron. Manag' .• 3, ~1-50,

Ch.ptn, F.S...nd Van Cte'·e. K. (1981) PI.nl nutrien, .bsorplion ,nd re'ention underdiffering fire reg'mes. ,n II-A, Mooney. T,M, Bonnock..n. t' L. eh"'tensen.J .E. Lotan.•nd W.A. Rein'" (ed.). Firt X,gimes "na £ros)'sltm I'r"pmi". USFor, Se", . Gen Tecli. Rep. WO·16. W..h,n~ton. DC. pp. JQI-321.

aa'k. F,E. (1977) In,ernal o)'ohng of "Ninogen In 'hon.gross proirie. Ecolog) , 581322-1333.

Cr~m. H, (1973) ~losse, of the Great Lake, fOfeli. COn/rib. ffIJm 1M Univ. of M'Ch.H"ba""m In. 1-4(U. Uni",,,,,')' of Michigan Ann ArhoL ~lich;g.n

151

Cu.tl",... C.T.. M.nm. R.E .. and Milkr. R.L (1968) 1ht dfcel> 01 fire On ",.dg~rmlnllion.l. RIm~' M~n~IC.. Zl. Z5(}-l>!.

D.ube,mire. R. (19681 Erolog)' 01 flre in gr",land'. Ad". £,uI, Rd .. S. 1W-266,no""dlng. E.S. (1919) Th. "'&<,"lion of Albena. III. Th.....ndhill a,," of ctn"al

Alben. ",ilh panicnlar rd.""". '0 ,h••rolo~)' of A,<,<u,hob,um amen.onum. J.Erol. 78. &2_103

Flinn. M.A. and Wem. R,W (1'171) D<:pth 01 on<lcri'O"nd plan' Of~'"' and,heof<lic.1 ",,,i,·.1 dunns fir<. C,,", J. S",.. ~S. 25SO-~55-l

FOITe>1. 0.1. (1971) SUuClOr< .nd productIOn 01 Non" P.nn"", bI.nk., I:>og'·.ge'ation. J. Ecol.. 59. ~53--4J9

0,11. A.M. (1981) Fi...d.pl",. If.'ts o( I·."",lar pl,n". ,n H.A Moo",,;. TMBonn"k"'n. N L o.,i".nsen. J.E. Lo"n. "nd W.A. ReL"" «d,). flf<Rtgim<J and Eco'J""<m Prop",i". US For. 5<" . Oon. Te<h. R.p. WO·~6.

Wash,ng'''''. DC. pp. M-230.O"m•. J. P, (1m) E.-iden« (0"'" <X'''On« 01 'hreo prim.') .. ra,o~,.. in pl"n" .nd

," '.~'..n« 10 .rologlcal .nd <\'Oln'lOn.'} 'h.O')'. A '. Na/.. 111. 1169-ll~.Grubb. P.J. (1m). Th. m.,n1<n.n« 01 '!'Cci., ""hn in p1.nl commun,"'" ,he

,mpon.oo: oIlbe rel."","10/1 n><h•. Siol. RtI,.. 5~. 107-145.H.I•. ~t.E (1969) Th< U.h"". Wm C. Bro",n Co. DohuqLl<. 10-..". ~26 ppH'fJ><r. J.L (1m) Popula""n Riolos>· of Plantt. Ac.domic P",", N'" York m

WHoinselm.n..\t.L (1973) Fir< in lh. I',,~in fort,,, of ,h. Boondary Walers Canoc

Arta. ~linn,,",a. QUal R.." J. 329-.l&211.inselm.n. ~'.L (1981) Fire inl.n'il)· and froqo."")· •• f.01O", in ,h. di"ribn,ion

.nd mllClurc 01 ""nile", o<:o»','.m,. in ILA Moo",,)'. T.M Bonn,ck",n. N,Lo."".n><n. J. E. Lotan.•nd W,A. R.i ...." (cds). fi" Regi...... ,,~d £«n,-"""Pro~"'<s. US For. So" .. Gen. Tech. R.p. \>,"0·26. ""••h,nglon. DC. pp, 7-57.

lohruon. E.A. (l9J5l Bon.d se.d popnl'lI"'" ,n 1he 'obar01" fOf'" .a" 01 0,..,SlaI~ Lako. Solth...." T.rri'orie,. Ca~. J. Bo'.. 5J.1933-1941

lohn>on. E.A, (19'19) Fire 'O"turon« in 'he ,ub.retlC and ,t; 'mplica"on' for'·'&<la'ion compo<l1ion. Can. J. BOI.. 57. 137"'1379.

K••I<)'. J,E, (1981) Fi" regim.. "nJ reprodUCli,~ cycles, In H,A \'ooo<y. T\l.Donnick"'n. N.t. Chmltn><n. J.E. lo1.n. "nd W.A. R.'...." (.d,). f";"Regi"''' and E""""jl<", Pro~"~. US For. 5<" Gon. Tech. R<p. \\'0-26.Wa.tl""lOn. DC. W 2."l1-2n.

K,il. AD, ••nd Ori~.I. J,E, (196'J) 1ht Ma) 1968 forn' conflag'ation in ",ntr.1Alben" a "",",,' of fir< "'.•• ,....'. 10.1, and fire bella'io,,,. Can. f"lN. Mn . Inf.R<p. A·X·N, 26 W

Kilgore. B,M, ••nd T'~'I0,- D. (1979) Fi,e lii"o'} of" ..qoo'.·m...d conif., 1'''<>1.Ecolo~y. 60, 129-142

Knight. D.ll . and Louoh. O.L. (1969) A quant'tat"·o .naIJ-,i, of WilCOn"n for«1".g.'ation on ,h. I>a<i' of p1anl fooction and g"", morphology, Ecolog)'. 50.219-234.

Kourll. P. (1%7) LiJIIll1ing b<h3Yionr.nd IiJlltning fi'" in C.n.di.n foro"•. COM/Jtp. Fl>'. Ruml D,,'clop,. Fo', B,"....h PuM, 1/19, 3J 1'1'

Lotan. J.E. (1976) eo". serollny-fir< rel.uon'h'ps in Ind~.pol< pinc. Pro<:. ToilTimb<" Fh Ecol. Conf.. I~. U>7-~78

lotz. HI (19:16) Eco\oi:IC.1 .ffw, of fore" fl,., ,n ,h. ,n"rior of Ala'ka. US D<pAg,k.. T..h. SuU. 033. 121 1'1'.

L~Qn. t.J..•nJ Sticknoy. P.F. ('976) E.,ly \C~lal ,ucc."ion follo"'in& large~s:.~;~ Rocky Moun,"in "'ildlires Pro<' TaU Timb<" Fi" Ecol. Coni. I~.

'"Mark., P.L. (1914) The rote of pIn dlelf} (F,un"" p""'-j'I<'am". L.) in the

m'"nlen.rKe of st'boh'> ,n ""'them ha,d..-ood ~>".m,. Eo"'. MOJWtf.. +I.n~.

McArthur. A,G..•nd ebene),:> P. (I"""") The ch.,."."",ioo of fir., In ",Iation toecologlC.1 "lIdi••. A ' for. Ro.. l. ).6-45.

Mel••n. A. (1%9) Fir. , ,t.o« of for." "f'Oci<> a, iofillc"cod II)' root ,),1<11\,_ JRange ,lfan<lg<., 21. 120-122

Milk, .•\1 (1917) Rcopon". of bl,,< bucklebe,'}' '" pr.""rib<d fir•• in a "'."C'OMontana I."h·fi, fore>1. US fo,. s,.",.. R... Pap. IST·ISS. 33 pp,

Moo,.. J.M. and Wein R.W. (1m) Vi.hl< "'cd population' b)' ooil <lepth and"",<ntial';'. colonization .flor d;"urb."",. C..... I, SOl .. 5S. Z40S-2412.

M"",. E.H. (1959) Flora of AI1><"rra. Uni,-.,.;,), of Tomnro "'.",. Toronto. Ontario.~,.

~l"l<h. R,W (1910) Wildl.f>Cl fi,e, 'nd ."",>"om..-.. hypothesi,. EroIogJ. 51.liW>-1051.

Noble. L R.. and SI.,>",. R.O. (1m) P""·f,,e <lI<'CC",on of plan" in ~te<l"errone.n

eco>}·"em•. in H.A. ,\100"')'. and CE. Conrad (cds). Pro<:, S"mP"Jiu", on 'heEn,'iron""nu>! CO/U''iurn<:t> of fir< .nd Fu,' .llan.g,,,,'nl in .II,d"''''lntonfro,,-"'ms, US For. 5.<", __ Gen. Tech, Rep, WO-3. P!'. 27-36,

Ohmann. LF" .nd Grig.L D,F. (1979) Early 'O"'getation and nutrien' dynam,c>follo"'ing the 1971 Little Sioux Forest Fire in oo"he»t<rn :>!in"e"",•. fo•. Sci­.IIooog" ZI, 80 pp.

P,anka. E, (1970) On ,-.nd 1>:·.. I«1lOn. A_•. ,\'.1-. 1001.592-597,Qo,ck, CR (1962) R.,or£.~ of a £OO'"bert; populat",n aft., fire on matofO

lLmber. J. Fo,. 60. 100-103R.unki'<r, C (1934) Th, Lfe fo.ms of P/nn" and Sla,"'icnl Plam Gros.aph)"' Being

Ihe Cnll«kd Pop,,' <if C Rau"kiM', G.rendon Pte"- a.,ford, 632 pp,Ritchie. l.e. (1959) The '·.J<tOliOll o! ",,"bem M.nitoba. 1ll Studi'" ," the

'ub,mi<. Amic In.t', North Am". T«h. Pope. '\"0, 3. 56 WR""., J.S (19790) Large fi,., in the large I,nd><:.p<s of the Nonh. m fiFt

,\fanas"",", in Ih' No.th,." E""i,o",,""' Simpo,,,um, US D.p. Interior. Bure.uland Man.ge .. AI a. Pt"",. 79-01- pp. 8-32.

R""., J-S. (19791» R••" ..-o'k,n, paper on methodolo!l; phrlosoph}' of eroloJ",alland d......fication in C..nad... ,n C D.A. Rube< (.d,) Applicaliom of fro/agica/(Bwph."ica/J La"d Clnnifi<lHiO't in CnMda. Eooiol!i<al Land O,,,ifi<>lioos.e,ics NO.7. Land, Drre<1or..<, Em'ironmen' Can'da. 01...... 1'1'. 23-:l8,

Ro..·•. l.S .. and Scone,. G W, (1913) Fir< in the oo.eal fore,'- Qua'. R". 3. 4--l--l-lt>lSdlocnike. R.E. (1976) Ge<>ir>phical ",riat;O'" in jack J'in. (Pm", btm/aidM). (in"

.11,,,,,,,,,,,, Alrn-. F.>cp. Sm.. T«h, Bull, J(J4 H 1'1'.SdIOCnik<. R,E .. Rudolf. T.D .. and Schanll-H,n..n. T, (19S9) CO"" ehar:><t<m'ic>

,n a jack pi""...,d ",u,,,, pl.nt.toon. Minnes",. fo., SOl" '\'0, 76, l.ke Stat"Fo,. &1', Stn. St Paul. Min""",,,. 2 pp.

Scott.,. G. W. (1961) Elf= of tore" fi .... on ,he .. ,nter tani< 01 barron-poundcaribou ,n oorU>ern Sa.ka"h",·.n. C"". Wr/dl. Srn "',MI. Mona". B.II" &,I. ,\0. 18. 1111'1"

Scott.r. G.""', (1972) Fi,. a••n «ologic.1 ta<tor tn bor••1 fo,." «",}',«m. ofCiln.<!a. ,n Fir< In ,he £n,·jTO"men,. S-"mf'O".m Prrxudmg•• US Fo,. Sc"'"Pub!. FS-276. Den¥u. Colocado. pp, 1S-24

ShafL M.I .. 'nd Yun.nton. G.A. (1973) Vegetational h<1<fog.""1lj' durrng a..ron<lar)' (postfifC) ,ucr.,,,on. Can. 1. 80,,51.73-90.

Si,fn. G, (1955) Th. de>'.I"I'mont of 'pruce forr" On raw hum", sit., in nonhornFinl.nd and its 0001°3)'. A"" fo•. Fenn.. 61. 1-lOll.

'" Thr Hair of fire in Nor/hern Circumpolar E(I>$F"ms

Sk"t<~. E. A (19291 Earl\ ".ge, of p1.n, ,,,,,,,,..IOn f<lllo..,n~ (0,...,,' fi ..... , Eroiog}.10. 17H89.

Sml1h. c.c. (1970\ The ~,ol""on of pine >Gu,,,el, (T.millst'u' .... l.nd ronif'T>.Erol. ,\ftm()flr.• .Il). 359-371

Sm"h D. \l, . and Sp>.rhng. J. H (1966111>c t<mpo'>!"fO' of ""'f"". fi,., ,n Jac). PO'"bar«" I Th. \anation ;n t<mpo'''"1< "'ith time. II 11>e dfeets of '-egotallOnco,'or, ~'ind .peed and ,clati,'< humidi!; on fir< tempera'u'e•. Can. J Il()l., .u.1285--1298

S'oJdan. L.A. Smith. A.D .. and Bo>. T W, (lorS) Rungr Mmu'K,mNl'. lrd <dn.~'rGTa,,·-Hill. "<'" York 5321'1'_

Tande _G. F, ( 191'J) Fire hi>lOf~' .nd ,·<~<1ation panorn of <onik,,,u, fo,o>!, in la,p.""",ofllli r.rk. Albe"•. Can. J. BOI.. 57. 1911-1931

UUI•. E. (J9SS) ECological Effm, of fiT< tm "onh SK',d"h Fo,~". Almq,-i>t andW,hell, Boktr"k." Ah. Uw-al•. $",d<" IS PI'

\'on d<r Valk. A. G .. and Dam. C B. (197~) The ,01. 01 "'ed bank> ,n 'he >eg.taIo01l<h'""rn;e" of proiri. y..ul rna"""•. E<oIo~,. 59. 311_335.

Van lI.'gn<r. CE. (19'';;') Ag'<]'" di"ribu'i01l and ,I>< IOf'>I fir< ",",,1•. C~". JFor. R" , a. 2~227

\'an Wagn". CE (1978b) M.tric uni" and oon,·."';on fa"toT> for 10r<>1 fi,cGuan""••. C~n. for. Mn'. In! R,p PS-X·7J. 6 PI'

Van Wag""r. CE, (19791 Fu.l .. ri.lio" m l~' narurol f".<~'cl<d bor<al for<s,- on DQointiho (.d). 1"0<. In/'mo,. fi,.. MOM~,m'n/ \I·o.k<hop. Can, FOT, Sc" . InfR.p. 1'iOR-X-215. pp. 67---#<

\"<f.e~. l.A (1973) \\,Idfire ,n 'I>c ''''g. of AI..... Quo,. R".. 3. -1M-195\ ·1<reck. L.A ,and Dp""", CT. (11)19) Eroloti"al .ff""" 01 ,I>< Wrckc",h.m Dom<:

fire ncar Fairb.ank'. AI"ka. US fo•. Mn', G.n. T«h. R.p. P.\"\I'·9lJ. 71 ppVogl. R.J. (1974) EfI«', 01 fir< on gf3s>land,. in T T "ozl",,~ki. and CE Ahlgren

(.ds). fire .IId Eco',.,"m'. Academic P,...". " ... Y"'k. pf>, 139-19-1V<>JI, II. J, (1979) Som. b."c p,,,,,ipl., 01 gra"l.nd fi,. m.nagem.nr. Em""'"

\fono~,.. J. 51-57.\\crn. It.W and Bli». l.C (1973) Cbang'" on ATeli, E,;opho,wn ,u,,,,,,~

rommon"i.. fol!o"ing lif<. Ecolo~,'. .I-I. 8-t~2.Whir.. P.S. (1919) Pa",ro. proc<» .nd natu..1di,'nrb.aoc< in '·.gora""n. 8",. 11"

~5. ~:'9-199

\\'hi"akcr. R.Il. (1975) Commonw", oml Ec",-w.ms, 2nd cdn. Macmillan. 1'iC"Yor•. 3Il5 pp,

11.'00'.1-. G, T .. and Do,. R.J, (l9n) A .ommal} 01 ,he fiT< .rology >lud) 01 Que''''''!'ron inci.1 Pat•. On/o,;o .I1in"",. <>f \",. Roou... Q."iw Pro,' Pu,k Fi,.. Eeol,S'ud,' /I.eI'. \'0. 8. 39 pp

Zoek",,,,n. O. (l'Jnllnfiu~oc< ollor~>1 f,,~, on lhe norlh S"-w,sh ooreal fore>!.Oi~"•. t'J. 22-32.

Z.dr"""n. O. (19SI) Fore>! fir< fr'Gu<n"l .nd l<g<tation p...~rn Ln 'hcVind<l:iI",n V.II<)'." Sw.den dunns tho pa" 60() y<.I\. Acto Un",- 0"1""",,,SoL A. 20 pp,