1953 (3)T h i s r e p o r t presents t h e r e s u l t s of b o t a n i c a l f i e l d uork done i n t h e summer of 1.952 under t h e Coral ,!toll P r o j e c t of t h e Pacis'ic Science Board of t h e Natj.onal Research Council

ATOLL RESEARCH BULLETIN

No.

x i

The Land Vegetation of Arno Atoll, Marshall I s l a n d s by

William H. Hatheway

Issued by

THE PACIFIC SCIENCE EOARD

National Academy of Sciences--National Research Council Washington, D.C.

April 30, 1951

. . . .

he

^Land Vegetation o f &no A$&,, ~ a r s h & l ~ s l a n d a ^{' ' '}

.. . . .

SCIENTIFIC DJVESTIGATIONS

IN

MICRONESIA Pacific Science Board

National Research Council

. .

Wi. l l b m :I. Hatheway Haj:vw'd University

Caibc:.c!&, ~ l a s s a c h u s e t t s ~

. .

... ^, Jariuwy.

1953

T h i s r e p o r t presents t h e r e s u l t s of b o t a n i c a l f i e l d uork done i n t h e summer of 1.952 under t h e Coral ,!toll P r o j e c t of t h e Pacis'ic Science Board of t h e Natj.onal Research Council. The work was supported by funds granted t o t h e National Academy of Sclences by t h e Office of Naval Research. The f i e l d w o r k was c a r r i e d o u t w i t h t h e a c t i v e assista.nce of t h e

U.

S. Navy Department, t h e N i l i t a r y A i r Transport Service, and t h e T r u s t T e r r i t o r y of t h e P a c i f i c Islands. The m i t e r wishes t o express h i s thanks f o r h e l p received from Harold J a Coolidge, :Piis, Lenore Smi.th, and Miss Ernestine Akers. M r .

D.

W , G i l f i l l a n , D i s t r i c t Ad:n*k&?ator of t h e Trust T e r r c t o i y

a t Xajuro, and M r o J, E. Tobin, s t a f f ant:2sopolpgistj took e s p e c i a l in- t e r e s t in t h i s stxdy and assisteci greatly. The h e l p of Lt. Cmdr, CI IC, Brust, who arranged t o have put a't t h e d i s p o s a l of t h e author c e r t a i n re- sources of t h e Ua S. Navy, i s grateful!_y ackno~dledged,

S p e c i a l thanks a r e due t h e people of Arno, e s p e c i a l l y K i h e j L., F e l i x J., Tobu, Lajibili., Jemeliic, Jibloic

J.,

Abijai, Lakarim, jonag Nemot L*, J a j i n

F,,

Bingel, Jakalu, Saburo, Jon, Lauken, Overton, and Likotalc* A t Na.juro Raymond QeBrw., Konto S., and Bright 3eine helped me i n many ways.

I am indebted t o t h e followjng f o r stimulating discussions and ad- vice: F" R, Fosberg, 3, S t . John, E. L. Stcne, J r , , J ,

W.

l;Jells, D" C. Cox, ReW

.

Hiatt,, D, Strasburg, L. Nason, P, E, Cloud, H, Uyehara, 3 . 'I. Xoul,, Mary Kurai, I I S , Doty, N, D. Newell,

:.

i.loK5son, G. D. ,Shi;?n~an~ I. E.

Lane, and E, 11, Bryan, Jr, ^?;'. R. Fosberg has nac?e some adjustn::;nzs i n t h e b o t a n i c a l nzi1lli.s of t h e p l a n t s p e c i e s d

CONTENTS

Page

Fresh-prater S~fmps

- - - - - - - - - - - - ^{- - -} - - ₄₄

Secondary F o r e s t s of t h e I n t e r i o r of Arno Island

- - - - 47

mY80DUC TLCN

In 1952 78 percent of t h e land s u r f a c e of Arno a t o l l was under

coconut and b r e a d f r u i t f o r e s t s , both of which types were maintained a s such only by periodic c l e a r i n g of unrranted wild plants. With t h e exception of r e c e n t l y i n t r o d x e d weeds, v i r t u a l l y every species of p l a n t on Arno found a s p e c i f i c use

--

i n medicine, conskruction of houses, canoes, and im- plements, or i n t h e weaving and coloring of mats, t o mention only a few.

The p o s s i b i l i t y t h a t even wild n a t i v e species had been planted on some

s i t e s they occupied could never be overlooked. Obviously, Arnots vegetation was insep&ably l i n k e d ~ & t h i t s people. To the s t u d e n t who regards vegeta- t i o n a s simply t h e r e s u l t of t h e i n t e r a c t i o n of f l o r a and h a b i t a t , inhabited a t o l l s such as Arno can be e;tremely confusing. Cn the other hand, a study of t h e i n t & r e l a t i o n s 'of the people and the p l a n t s of an a t o l l i s i n t e r - e s t i n g & t only i n t h e i n s i g h t i n t o t h e l i f e of t h e a t o l l people which it provides, but - a l s o .in i t s i l l w h a t i o n of c e r t a i n important processes of vegetational and edaphic change which might othervise n o t be understood.

o bib out

1000 persons .were r e s i d e n t a t Arno i n 1952, most of whom l i v e d i n rLl.lages along the lagoon shores of the wider islands. Islands l e s s than 600 f e e t w i d e and stony lands were f o r t h e most p a r t uninhabited.

Dwellings rrere concentrated n e a r t h e lagoon shores of t h e wider islands, f o r these s i t e s , besides providing easy access t o the la.goon, were con- veniently near those areas b e s t s u i t e d f o r c e r t a i n food p l a n t s

--

^{t h e}

b r e a d f r u i t and the y a r a j (Cyrtospemia). In t h e i n t e r i o r s of t h e wider islands the s a l i n i t y of the ground water was s u f f i c i e n t l y low t o permit t h e i r growth. The v i l l a g e s , ho'wever, were n o t always conveniently near

coconut groves. Copra-making p a r t f e s often had t o t r a v e l considerable distances t o t h e i r worlc,

A t Arno r i g h t t o t h e use of t h e l a n d was held n o t by individuals

,.. . : . ^.

b u t i n s t e a d by extended family groups (btrij), the heads of which were ..

termed alabs. The l a n d holding ( r a t o ) was comaonly a narrow s t r i p O f

ground one t o k v e acres i n a r e a extending from lagoon t o ocean.

In

, . . .

many cases

a

^{b w i j} h e l d r i g h t s or. more than one +?to. ~ i o m i t s w%x

. . .. .. ... . ^. . . . . .

the hij harvested much of i t s food and woGd and all 'of i t s coprao The

. . . .

l a t t e r &oduce c o n s t i t u t e d the chief source of cash incorne t o t h e bwig, . .

. . .

from which i t s members purchased imported foods, clothing, soap, kero- .. ^..:. . . . .. ^.

sene, and other t r a d e goods, Land could n o t be bought o r sold; t h e

, ,

r i g h t t o the use of t h e l a n d was i a s s e d i n s t r i c t h e r e d i t a r y fashion

fro^,^ one generation of the brrij t o t h e next. Aside from a very small

. . . . .

a r e a claimed by t h e Lbited S t a t e s ~o&&iment, t h e r e was no public l a n d on hrno, Ri$t t o the use of each piece of land on t h e a t o l l was claimed by a t l e a s t one Mj. Consequently, it i s obvious t h a t t h e vegetation found on any piece of land was dependent upon the previous use of t h a t land by i t s &ij.

. . . , . .

I n t e n s i t y of l a n d use depended n o t & l y on tlA s u i t a b i l i t y of t h e

. . . .

l a n d holding f o r t h e growth of economic plants, b u t a l s o on such f a c t o r s a s i t s distance from t h e places o r residence of t h e bwij, t h e number of acres per h d j inernber, and very probably on t h e i r d u s t r i o u s n e s s of the members of t h e b i j , e s p e c i a l l y t h e alab. Ny a s s i s t a n t informed'me t h a t the b x i j of which his f a t h e r was alab, was unable properly t o talce c a r e of a l l t h e land rihich h i s t o r i c a l l y it had been a l o t t e d . "Some have too much land, Some don I t have enough." A t Najuro a t o l l brush had grown up on land occupied

by

the I h i t e d S t a t e s Government during the w a r and

since abandoned. The former IjIarshallese %wnerstl had by no means r e l i n - quished claims t o t h i s land, b u t were n o t c e r t a i n of t h e i r l e g a l r i g h t s t o i t s use. Land disputes vere a l l too common a t Arno, Since t h e author was advised n o t t o become involved in such disputes he did n o t i n v e s t i g a t e t h e i r r e l a t i o n s h i p s t o t h e intensLty of use of the land.

In 1952 the f l o r a of krno a t o l l consisted of about 125 species of vascular p l a n t s (cf Anderson, 1 9 9 ) . O f these n e a r l y h a l f had been i n t r o - duced ~ n t h i n t h e p a s t 100 years, roughly 3 8 i n t e n t i o n a l l y a s c u l t i v a t e d p l a n t s and 19 a c c i d e n t a l l y a s ~ieeds. That i s t o say, t h e Arno f l o r a of 1850 consisted of approfimately

68

species of higher plants. O f these, however, probably about 24 had been introduced by t h e Narshallese a s economic p l a n t s o r weeds. Although a n a t i v e f l o r a of approximately

h!t

species ma,y seem very small, t h a t of Arno i s r e l a t i v e l y r i c h compared t o the f l o r a s of other lai i s l a n d s s i t u a t e d a t g r e a t e r distances from the r i c h source of seeds of Malaysia and Nelanesia, o r receiving l e s s r a i n f a l l . Canton Island i n t h e Phoenix group, r e l a t i v e l y near t h e r i c h f l o r a of

. . . .

F i j i , has a n a t i v e f l o r a of only.

16

species, but i t i s n e a r l y

a'

desert.

.. . . ~ . . . . .

. . . .

Palmyra Island, lying t o t h e e a s t of Arno, receives about a s much r a i n f a l l

. . . .

a s t h e l i t t o r a t o l l , b u t i t i s nwch more remote from major sources

of

. .

seed. Its f l o r a c o n s i s t s of only 16 species.

. .

Although the f l o r a of lirno i s l a r g e r than t h a t of many a t o l l s , it i s

. . ._{. . . . . , .} . . . .

small and r e i a t i v e l y i n i n t e r e s t i n ; compared t o the r i c h f l o r a s of high i s l a n d s l i k e F i j i , Hawaii, T a h i t i , o r even Ponape. Not a s i n g l e vascular

. . , . ,

p l a n t species i s r e s t r i c t e d t o Arno a t o l l . A l l o f the n a t i v e mild species

. . ,. . . . .

a r e wide-ringing plants, most' occurring on t h e shores of i s l a n d s

i n

both

. . . ...

the ~ a c i l ^ i c and Indian oceans, and at. l e a s t

7 --

16 percent of t h e n a t i v e

. . .

f l o r a

--

occur n a t u r a l l y i n the t r o p i c s of both h e h i p h e r e s . ^' Excey~t f o r a

s i n g l e species, Pisonia ^.-.-.I grandis a l l of t h e n a t i v e p l a n t s ^{. .} of Arno possess seec'.s o r f r u i t s which a r e d i s t r i b u t e d by wind o r ocean c w r c n t s . The fruits of t h e Pisonia are glutinous and adhere t o t h e f e a t h e r s of t h e wide-ra?gi.ng seabirds which r o o s t and n e s t i n i t s branches, I t i s n o t siwprising, then, t h a t t h i s t r e e occws on n e a r l y every high and low i s l a n d in t h e P a c i f i c and Xn'jldian Oceans which i s s W f i c i e n t l y moist t o permit i t s growth, a s do, indeed, a l a r g e proportion of t h e other n a t i v e species of t h e Arno f l o r a .

The ciimate of Arno i s proba.bly n o t very d i f f e r e n t from t h a t of nearby

, . Hajuro, where annual r a i n f a l l i s of t h e order of 220 inches. The winter is

. . marked by stronger, more constant n o r t h e a s t t r a d e s and by somewhat l e s s r a ? a

.. .

than t h e s k e r , :lean annual temperature i s 81° F.; mean monthly teiirperatures

. .

vary only within 2' of t h e y e a r l y average. The dLurnal v a r i a t i o n i s about 1 0 0 ; n i g h t s a r e p l e a s a n t l y cool. _{.. .}

Arno a t o l l contained 133 i s l a n d s and i s l e t s in 1952, which formed

5

square miles (3200 a c r e s ) of d r y land, Almost a l l these i s l a n d s had t h e _{. . . .} same s t r u c t u r e . Their seaward s i d e s consisted of ridges of boulders,

cobbles, and stones thro:m up on t h e r e e f f l a t s by storm waves. Sand ac- cumulated on t h e lagoon s i d e s of t h e s e boulder ridges, anddunes formed where a sandy beach faced the ? r e v a i l i n g n o r t h e a s t trades. Between t h e

stony ridge of t h e ocean s i d e and t h e dune ridge of t h e lagoon shores, was often a.n i n t e r i o r depression. The i s l a n d s tended t o i n c r e a s e i n width by additions of sand on t h e lagoon side, and coarser m a t e r i a l on t h e ocean shores.

m e ground water of an a t o l l i s l e t i s characterized by t h e presence of a Ghyben-Herzberg l e n s of f r e s h water. The depth of t h i s lens and i t s s a l i n i t y depend on the distance t o t h e beaches and t h e permeability of the s o i l s , Stony land i s m c h more p r m e a b l e t o t h e salt water of t h e ocean

than i s dune sandg and with..the r i s e and f a l l of t h e t i d e s x2preciable mixing of f r e s h and s d t water occurs. Thus t h e stony land of the ocean

s i d e of i s l a n d s is underlain by much more s a l i n e ground water t.han lagoon- shore dunes. .The ground water i n t h e . i n t e r i . o r s . . ~ . f . t h e . . ,.. wider i s l a n d s i s remarkably f r e e from s a l t . Cox (1.951) found only 8 ppm chlorides in. a well a t Ine about 500 f e e t from t h e lagoon;..,.,^: +I> inter&or pool on Tatu

Island only 200 f e e t from t h e ocean I f o . w d . . , o n l y . l , ~ ppm, 3-50 f e e t from

t h i s pool t h e ground water i n t h e boulder rampa"t,iiad a chloride,col?centra-',

.

.

t i o n of 7100 ppm, about 470 times a s great. Fosberg (1949) qd,.Cox re- marked t h a t ground.-mter s a l i n i t y apparently a c t s as an e f f e c t i v e c o n t r o l

on t h e d i s t r i b u t i o n of t h e b r e a d f r u i t , an economic p1:ant o f a b o r i g i n a l introduction. Variations in s a l i n i t y a f f e c t t h e , d i s t r & b u t i o n s of s p e c i e s of t h e x i l d n a t i v e f l o r a a s well; t h e tolerance

:to

, . s a l t of species of t h e Rhizophoraceae Pemphis acidula, and o t h e r s i s J . of - c o w s e ,

well 1nor.n

.

^{. . . . . . .. .}

A s Stone (1950) and Wells (1951) pointed out, t y p h o q i , o c c u r about, ^{: :.}

4.

times per century a t Arno, and have l e f t t h e i r ma.rk on. t h e i s l a n d s i n

.

many m y s . The washing away of e n t i r e i s l e t s i s a spectacular consequence of typhoons, b u t windthrow and p a r t i a l inundation have a f f e c t e d s o i l and vegetation. In c e r t a i n l o c a l a r e a s on Kilange Island, f o r example, n e a r l y

every l a r g e b r e a d f r u i t t r e e was blown dovm in t h e typhoon of 1918 and

l a r g e q u a n t i t i e s o f s o i l were t h u s disturbed. B o t h e r places considerable amounts of sand and rock had been suddenly :dumped on low, land, o r t h e

s u r f a c e l a y e r s had been washed out, Such areas v e r e o f t e n c l ~ a r a c t e r i z e d by low organic and n u t r i e n t content. of t h e s u r f a c e horizons.. Themore s u p e r s t i t i o u s believed such land t o be inhabited by malignant s p i r i t s which hinder t h e growth of p l a n t s , S t o r i e s of h a l l u c i n a t i o n s caused by these demons Irere common.

- < -

Relatively minor changes were c o n s t a n t l y occurring along beacheso Betrreen Ine and ?.Iatolen, f o r e x a q ~ l e , the shoreline was eroding i n

places, and p l a n t s which formerly grew along low dune r i d g e s were stranded on t h e beach. A Perphis t r e e with s e v e r a l pebbles embedded i n i t s %rood 3.2 f e e t above t h e present l e v e l of t h e ground was discovered growing on a

sandy beach

1s

f e e t from an e r o d h g dune containing s i m i l a r pebbles near i t s surface. The t r e e had i n e f f e c t noved 15; f e e t toward %he lagoon during i t s l i f e t i m e . Near Lukwsj coconut t r e e s , which had previously toppled onto the beach a s t h e dune upon which they were growing was undercut, were being covered with sand a s the beach again b u i l t up. lWtire t r m k s were buried save f o r t h e e r e c t terminal p a r t s , about 5; f e e t t a l l . The leaves vere n e a r l y twice a s long, and some t r e e s were bearing heavily.

Thevegetation of Arno a t o l l i s here c l a s s i f l e d i n t o ' $ types (Table I).

. .

These a r e merely a r b i t r a r y groupings of aggregates of p l a n t s i n t o ?.inits con- venient f o r description, analysis, and :mapping, This, however, ' i s n o t t o deny t h a t i n t e r r e l a t i o n s m i j r be found betveen p l a n t s growing near one

. .

anotker. The v e g e t a t i o n a l inaphas'been dravn from 191ik-19h5 a e r i a l photo- graphs taken by t h e United S t a t e s & q r , supplemented by ground observations and i n t e r p r e t a t i o n of oblique t a k e n by t h e Navy i n 1952. In general, t h e vegetational types lis'ced

i n

^Table I a r e only those'trhich could

. .

be distinguished c l e a r l y on t h e 'a6ri.d- phdto&aphs. ~ h u s ttscrub f o r e s t "

i s mapped a s a s i n g l e u n i t , b u t i s divided i n t o 1~ subtypes i n the descrip- t i v e t e x t . Boundaries between t h e types are, of course, no l e s s a r b i t r a r y than t h e types themselves. Even' on t h e grotmd i t i s n o t always possible t o c l a s s i f y with c e r t a i n t y a s ~lcocon& type11 o r "scrub f o r e s t " a s t a n d of small, wild n a t i v e t r e e s through % h i & cocbnd"trees ^'

@!ejected,

Bread- f r u i t groves were usually characterized by a rank undergrowth of n a t i v e

t r e - s and v h e s . "Secondary forest", O i l Arno i s l a n d contiguous with extensive " b r e a d f r u i t ~ r o v e s l l , u s u a l l y contained numerous b r e a d f r u i t t r e e s . Obviously a l i n e s e p a r a t i n g "secondary f o r e s t " from % r e a d f r u i t grovet1 r u s t be based.to some degree on a s u b j e c t i v e e s t h a t e o r i n t e n - s i t y of use, i l l ~ ~ s t r a t ' n g t h e f a c t t h a t on .kmo vegetational study was inseparable from c u l t u r a l anthropology,

. . . , . .

TABLE 1

. .

m e

-

^{?!umber '} o f Stands

-- -

Acres Average s i z e of stand Percent

(acres)-..-- --

-

Coconut

Productive Laora H e l l a l Breadfruit Scrub Forest S a l i n e F l a t iiangrove Swamp Fresh-rrater Srramp Secondam F o r e s t

Total

COCONUT TYPE

P r i m r y species: Cocos n u c i f e r a

IJeight of t r e e s : 40 t o 50 f e e t , exceptionally t o 80 f e e t

Density: about

95

t r e e s per acre, exceptionally a s low as 40 O r a s high a s 11~0 t r e e s per acre.

69

of t h e land a r e a of Arno atoll. was under coconut f o r e s t i n 19.52, f o r c o p r a r"omted t h e main a r t i c l e of export of t h e a t o l l . Copra was f e a s i b l e on ? r z c t i c a l l y t h e e n t i r e land surface of the a t o l l , s a l i n e f l a t s and svaxps and c e r t a i n p a r t s of t h e i n t e r i o r s Of

wider i s l a n d s forril& the only s i g n i f i c a n t exceptions t o this r u l e . The vide i n t e r i o r s of islands, however, were devoted in l a r g e measure t o

food production f o r l o c a l consumption, and t h e exceptionally r i c h phosphatic s o i l s of Takleb and Namwi had been given over t o soine degree t o such

s p e c i a l crops as Kapok, Tapaya, and Banana. Remote, narrow, o r Stony lands, areas i n which t h e arnershLp of t h e land was i n dispute, o r 1.ands t h e

workers of which were l e s s e n e r g e t i c than others, i n soine cases supported stands of wild n a t i v e t r e e s ,

The coconut t h r i v e d over an e:?tremely wide range of environm€nta.l

. . conditions. It bras productive over a 1,000-fold range of grouna-wafer s a l i n i t y and over a t l e a s t a SO-fold range of concentration of aval-lable phosphorus. It was found on a l l h a b i t a t s from fresh-water smmps t o dry, windmeptdunes, on organic mucks, f i n e o r coarse-text~&ed sands, o r among fragnents of c o r a l rock. Ecbept on those few a r e a s i n which it Tras not productive, t h e coconut ms u t t e r l y worthless a6 an i n d i c a t o r of environmental differences.

The p l a n t s which grew under t h e coconuts, however, were n o t always t h e same in t h e d i f f e r e n t h a b i t a t s on which t h e coconut was planted.

Consequently, it i s convenient t o recognize t h r e e environmental subtypes within the coconut type, corresponding t o the 3 major physiographic

divisions of an a t o l l i s l e t . 1. Lagoon shores and dunes

Secondary species: Pemphis acidula, Scaevola frutescens,

-

⁸

..

Hernandia sonora, Calo~hyllum i.nophyllum, Harringtonia a s i a t i c a , Suriaaa m a r i t i m , Pmdanus t c c t o r i u s , Sophoi.a koinentma, Canaval-La i,licyocarpa, Ipomoea tuba Ground layer: Lepturus repens, Fim'oristylis atol-lensis,

Thuarea involuta, Cassytha f i l i f o r m i ~ ~ Triuinfetta procmbcns, Vigna marina, Tacca leontopetalo:des, I'olfiodium scolopendria, Kuphorbia chamissonis, Canavalia serjlcea

The coconut t r e e s usilally overhung t h e lagoon, sometimes toppling onto t h e lagoon beachwhere the. s h o r e l i n e was eroding. Along the lagoon shores of t h e leeward i s l a n d s Pemphis acidula, a much-branched

--

1011 t r e e rrith exceedingly heavy, hard >bod, iias o f t e n abundant on exposed beach- rock. In o r n e a r v i l l a g e s Hernandia sonora and Calophyllum inophyllur~~

-- --

were observed, t h e l a t t e r conunonly befing used f o r r a i n catchment, C n dunes Lepturus, Fimbristylis, and Thuarea formed a low, dense cover under t h e coconut t r e e s .

Lor? I n t e r i o r s 2.

Secondary species: Morifida c i t r i f o l i a , , P a n d a n u s t e c t o r i u s , and o t h e r t r e e s of t h e scrub f o r e s t type,

. . . ^{. , . .} . ^, . ^.

C-round l a y e r : Lepturus repens, F i m b r i s t y l i s a t o l l e n s i s 9 Thuarea involuta, Vedelia b i f l o r a , Cassytha. ...

f i l i f o r n r i s , Triumfetta procunlbens, Vigna

.. . . . . .. ^' - ,'marina, Tolypodiun scolapandria, Euphorbiahetero-

phylla, Tacca leontopetaloides, Aspleniun nidus,

. . .

. . . Nephrolepis:,sp. Boerhavia d i f f u s s . . . .

; F i m b r i s t y l i s . a n d t h e grakses.! grew t a l l e r here, and Pan@.mus, s p r o u t s of iiorinda, G~iettarda, and o t h e r t r e e s of t h e scrub forest:foxmed jungles in some poorly tended groves. E p i p h y t i . ~ mosses, I\rephrolepis, and Aspleniutn appeared on stumps, f a l l e n logs, and rocks. .The v e l o c i t y of t h e wind Was much reduced and t h e h a b i t a t seemed moister, . . .

Boulder r i d g e s and stony land

---

Secondary species: Trees of t h e scrub f o r e s t type . . .. . .

Ground layer: Asplenium nidus, Nephrolepis s p , ~ , Wedelia bf.flora, Polypodium ph3;matocles, Fiiiibrist;'l.ir; ato:Llensis, Lepturns repens, Triumfet'ca procumbens, V l y a marina, Thuarea involuta,

Ground cover tended t o be s p o t t y mong t h e rock fragments of boulder ridges; l e s s than

5

percent of t h e ground might be covered rrith vegetatjon,

The f e r n s Aspleniurn, Eephrolepis, and Polypodium,. together r : i t l ; patches of Wedelia i n openings, rrere perhaps t h e most abundant plants. Invasion by trilcl t r e e s from stands of n a t i v e f o r e s t along t h e ocean necessS.tated n e a r l y c o n s t m t clearing, and in many places t h i c k e t s had groin up t o such

an e x t e n t t h a t c o l l e c t i o n of f a l l e n coconuts was i n p r a c t i c a b l e . Types of Poor Coconuts

-- -

⁷

About

4

percent of t h e acreage under coconuts on Arno A t o l l rras r e l a t i v e l y unproductive. The iIarshallese recognized two types of llpoor

coconuts:~l ItLaorat1 and tWellal." Each had a f a i r l y c o n s i s t e n t s e t of _.

,

c h a r a c t e r i s t i c s which, with p r a c t i c e , could be r e c o g n i z e d e a s i l y .

1,

llT,aoralt on Arno a t o l l occurred on Arno i s l a n d and i n t h e b r e a d f r u i t b e l t i n Ine village. In i t s extreme form on Amo i s l a n d "LaoraI1, Tias c h a r a t e r i z e d by:

Yellowing and scorching of t h e l e a f l e t s of t h e coconuts, most severe a t the t i p s e Areas adjacent t o t h e midribs were u s u a l l y green,

. .. The l e a f l e t s were sonetiines twisted and more o r l e s s knotted together,

.

Dead leaves tended t o hang on t h e t r e e ,

The trunks of t h e coconut t r e e s v e r e sometimes blaclcened,

i Density of stoclcing was 1 0 1 ~

--

^{about 40} t r e e s per a c r e i n t h e worst a f f e c t e d areas of Arno island,

. Dead t r e e s were conspicuous, About

35

t r e e s per a c r e were dead i n t h e worst a f f e c t e d a r e a s of Amo.

The o l d e r t r e e s were mostly barren of f r u i t , although t h e y produced

-

^{10 n.}

inflorescences. Apparently t h e f r u i t s aborted a t an e a r l y s t a g e of

. , .. . . .

. . ^{\ . ,. . ..} ..

development

The younger t r e e s bore f a i r l y well; t h e i r water was exceptionally sweet.

.

In t h e xorst a f f e c t e d areas of Arno i s l a n d the ground cover con- s i s t e d of clumps of Fimbristylis a t o l l e n s i s covering t h e ground between

-

^J--

which was a l e a t h e r y black blue-green a l g a resembling a crustose lichen.

Tacca leontopetaloides was common, Its l e a v e s w e r e yellow except along

- -

the veins and were characterized b y the pgesence 'of ' c i r c u l a r brown spots

: . , ' . . . . .

.

^{. .} ,

.

1/8 t o

l/k

^inch

ⁱⁿ

diameter.'

. .

-

Laora was r e s t r i c t e d t o the i n & i o r s of t h e wi.d&fsl~'ds, ?,here

it

. . . . . . . . .

occurred on s o i l s of t h e Arno ser5es. ^{. .}

, . . . , . . :

The Arno people' a t t r i b u t e t i %.orall t o a !'lack o f &lt.!' I t i s t r u e

, . .

t h a t a r e a s on which t h e &lady w& &&sent contained Gery l i t t l e sodium

. . . . . . .

chloride in t h e ground wht&P. ^. ~ r o d u c i i v e coconuts, however, occurred on

, * : . . . . , .

sandy

sbils

no l e s s d i s t a n t fr;nlagoon and ocean and thus probably con- . .

taining no more a v a i l a b l e sodium. It w i l l be n o t i c e d (~ig.

13)

t h a t t h e area of poor coconuts on Arno formed a Semi-circle aroundan' a r e a of

.,. . . .

secondary f o r e s t containing numerous' 'abandoned house-sites A d y a r a j (Cyrtospcrma) p i t s . On small c l e a r i n g s within t h e secondary f o r e s t t h e

.. .

coconuts i n v a r i a b l y exhibited severe i'laorau symptoms. 'As one proceeded

. . .

r a d i a l l y from %he' former center o f ' h & i t a t i o n immediatbly dn th* iagoon . .

s i d e of the y a r a j p i t s , the malady appeared t o become progressively l e s s severe. It i s t h u s possible t h a t t h e poor 'growth of coconuts i n p a r t

. .

of t h e i n t e r i o r of Arno i s l a n d i.& r e l a t e d t o t h e i'ormbr use

of

the land

. . . .

.

.

^{) ,} . .

f o r hum& habitation.

: . . .

. . : . . ~ . . .

2. 1~;3ellal", unlike tllaora,ll occurred a t

or

near t h e shores of 3.sland.s.

Its distinguishing f e a t u r e s were :

General yellowing of t h e leaves of t h e coconuts<. New leaves were slmr t o turn green.

The palms ap.peared s t u n t e d and ~jiobably died e a r l y ( t r e e s i n

.

^{. . . . ..}

l a o r a areas were often very t a l l ) .

-

Dead leaves did n o t f a l l r e a d i l y , The t r e e s bore only a fe'ir nuts,

Ground cover was i n v a r i a b l y depauperate, consisting c h i e f l y of . . .

an open stand of bunchy Lepturus repens.

. .

The p a r a s i t i c vine,

---

^Cassytha

-

f i l i f o r m i s , was u s u a l l y abundant, . ,

I n t s i a b i j u & grew a s a s t r a g g l i n g shrubo although on b e t t e r

. . . . . . . .

s i t e s i t be&& a t r e e 60 o r more f e e t t a l l .

. , . ^{. .} , ^{. . ,}

~olypodium scoloplndria was often common.

. . . . . ^{. .} _{. . .}

~ e l l i l occurred a t o r n e a r t h e lagoon or ocean shores of islands,

' T

.

^.

on immature s o i l s of t h e Shioya series,,

. .. . . . .

. . .

S t o n e . s u g g e s t e d t h a t t h e poor growth of these coconuts might be a t -

. :

t r i b u t e d t o sodium t o x i c i t y . A n a l p i s by t h e present author of t h e ground

. .

r.rat& i n an a r e a of llmellalfl on Langar i s l a n d demonstrated only 135 ppm,

. . .

chlorides. Judging from t h e r e l a t i v e l y s l i g h t accunulation of organic matter i n t h e i r upper l a y e r s , t h e "mel.lalr1 s o i l s appear t o be young, and

,

may have r e s u l t e i from washouts o r heavy deposition of sand during ty- phoons. It i s here suggested t h a t many mellal s o i l s may be d e f i c i e n t in n i t r a t e s , b u t t h a t these d e f i c i e n c i e s probably do n o t become s t r i k i n g u n t l l nore than 30 years a f t e r t h e o r i g i n a l deposition of a s o i l o r t h e exposure of a f r e s h surface i n a typhoon, Areas washed out during t h e

1918 tmhoon supported a p ~ a r c n t l y vigoyous stands of young coconut t r e e s , A legend s t a t e d t h a t t h e lehe13.alu a r e a of Langar i s l a n d vas buried m d c r

. _{. . .}

'sand deposited during an a m i e n t t b h o o n . Ine::cavating a p i t t o t h e . ^\

- I

water table, however, t h e m i t e r encountered no buried p r o f i l e s o

. .

~conomics of Copra ~ r o d u c t i o n on Arno

---

. .

--

~. . ..

The p r i c e of copra has fluctuated djid.eiy s i n c e 1950.

m. ^K.

E.

Blodgett, manager of t h e I s l a n d Trading Company, Majuro, pzid t h e follow-

. ..

.. ,

ing"&ices ton of copra 'delivered (on ITC t r u c k s ) a t Najuro:

. , .

Jan. 1, 1951 110

, ... .

Feb, 10, 1 9 9 , 1 3 0 '

June 16, 1951

115

,.. , :,,_{, . .} . . .

Oct. 1, 1 9 5 , ^' 105

. . . , . : . , , . . .

Jan. 1, 1952 95'

April 1, 1952 70

July 1, 1952 ^{. . .,:} 70 v : 7 ~ .

Sept. 1, 1952 70

. . ...

The 1952 p r i c e of

3&

p e r pound, a f t e r f i x e d c o s t s .were deducted, l e f t very l i t t l e f o r t h e "ri j e r b a l " (workers). The chief c o s t s were:

Share of t h e i r o i j Id, Share of t h e a l a b 0 0 4 Shipping c o s t s (Arno-Na$iro) 0,7

Total 2.1&

- .

.

^.

_

^{I: .. .; '}

,

That is, a t the p r i c e of

3&

per pound, the r i j e r b a l nett'ed'only 1& per pound (!:28,00 per ton). The share of t h e i r o i j tras fixed; it d i d n o t . f l u c t u a t e ~ i t h _{. . .} t h e p r i c e paid by ITC-31ajuro. _{, . . .} I believe t h e game

. ~ , . . . _{. .} ^. .

was , t r u e o f

$he,

share of t h e d a b a . ^:

. . . . . ., , . . . . . . . . . .

A t t h e r a t e of

I$

p e r pound of t h e 622 tons of copra s o l d a t I.lajuro,

. .

income of t h e i r o i j of Arno i n 1951 was about $129:100, o r

1,:5,!%

per a w e of coconut land, Although the p o l i t i c a l and s o c i a l p r e s t i g e of t h e r o y a l c l a s s e s of the P13rshall Islands i s s a i d t o have declined .(spoehr,. l?49), t h e i r economic p o s i t i o n has probably improved with t h e introduction of t h e copra trade, it The r e l a t i v e l y l a r g e income derived from lkent'l of copra land may have been a primary consideration i n t h e r e v o l t of t h e t h r e e

, .

. ^{. . . .} . ,: . ,

i r o i j e r i k of L i w i t o (ilason, 1952). In 1952 these men i n e f f e c t con- sidered themselves i r o i j l a b l a b on a t l e a s t p a r t of t h e i r l a n d

--

^{t h a t}

i s , they demanded ( b u t did n o t altgays receive) t h e share of t h e i r o i j _{. .} on t h a t land,

. . . .

In 1951 I T C Majuro purchased 622 tons o f c 9 p r a ^{. .} from Amo a t o l l .

.. , , , ,.

This copra vas produced by about 216,000 trees.

. : . . :

TABLE I1 Type Estimated coconut t r e e s

per a c r e Coconut

... . I . ,,;:

95

_{.,, ., ,,}

, ' . . .. ^{: .} . <

. .

! Acres ' ~ o t a f G e e s

e . ,,.; . ^{. . . ,} . . ^{. >} *. ., ^' ). , .. ^{i ' ,}

Breadfruit 1.5' _{/ '}

Scrub F o r e s t

5

Pandanus s w n p

45

Secondary f o r e s t 10 Total

\ .

3tA considerable proportion of t h e copra share of t h e i r o i j was s e t aside by t h e council of alabs f o r t h e payment of extraordinary medical expenses incurrcd by Arno residents. The p r e s t i g e of the i r o i j , however, was

probably n o t lessened by such philanthropies, however i r v o l u n t a r y they may have been.

I n shipping copra t h e d r i e d coconut meatwas s t i d f e d i n & coffee

~.

bags. The contents of about 350 n u t s were strEficient

t o

fill one bag, which then averaged about 106 pounds in weight, That i s , t h e contents

of a s i n g l e nut, when dried, weighed abont 0.303 pound on t h e average.

It folloris t h a t t h e contents of

L o l l

x 1 0 nuts produced on 2.16

6 x

1 0

5

t r e e s mere exported t o Majuro in 1951, Thus, t h e average number of r i p e n u t s h a v e s t e d f o r copra was 19.0; 0.28 tons were produced per acre of coconut land.,

Local consumption of coconuts a s food i s here estimated from t h e Majuro d a t a of Spoehr (1949; p.153). In 1947

58

persons belonging t o

. .

7

households consumed i n 21 days 1083 n u t s and 607 q u a r t s of coconut toddy ( jukaru)

.

^{It i s} d i f f i c u l t accurat& t o estimate t h e "aquivalent of t h e toddy in nuts. Copeland (1931) s t a t e d t h a t

5785

coconut t r e e s in t h e Philippine Islands produced an average of 0.65 l i t e r per t r e e per day i n t h e y e a r 1909-.1910. In malcing jukaru an inflorescence of the coconut t r e e i s c u t off and t h e s a p dripping from t h e c u t s t a l k i s c o l l e c t e d over a period of 2 t o 3 weeks. Assuming, conservatively,

. . ^: . , . . .

t h a t ' t h e ikflorescence would have produced

<

^{&t;s had it} n o t been cut, . . . .. _{. .} . . _, . . . _. ... ,

one qua& of jvka.$u i s app!:c:~:imat'ely e q u i ~ c i h n t t o 0 , 4 nut. Thus t h e

. ., .. . .,

.

^{. . .}

t o t a l cons&&ion of co&~.~v.t brodi:cts as food repcr-bed by Spoehr was

,

.

_{, .} . . . . . . : . . .

approximately t h e ey~~2::nle.n5 65

1355

nu%s, o r 1 , L coconut p e r person

. . . . . . .

. , . .

per day. 1 _suspect Ynl?; f i g u r e i s consexira.tive 5.f appl.5,ed t o h o e

. .

Majuro v i l l a g e was crowded rri* wir r e f : y e w i n J.S-'ir:l, when Spoehr made

. .

his study, and coconuis w?re ;nroirrAly i n sx:c?:l; s,;ppiy, Accepting t h i s

. .

f i g u r e a s being of t h e correc-i; order of rii~lg~itude!, howe-~er, t h e t o t a l l o c a l y e a r l i consumption of coconuts a s food a t Arno i s about k00,000

nuts, o r about

1-85

n u t s per bearing t r e e e Nuts processed local3y f o r coconut h a i r o i l and massage would p ~ o b a b 1 ' ~ b ~ i n g t h e f i g u r e t o 2 nuts' p e r bearing tree. This t o t a l i s t h e equivalent of about 60 tons of copra,

Summarizing these data f o r l o c a l and export production, on Arno a t o l l about 21 n u t s were harvested per bearing t r e e i n 1951, t h e equivalent of a production of 0'31 tons of copra per a c r e of coconut land. How do these f i g u r e s coypare with those of other copra-producing areas? Webster (1920: p,h3) s t a t e d t h a t Itowing t o close spacing and no c u l t i v a t i o n , t h e average annual y i e l d per t r e e i n t h e Philippines i s estimated a t 25 nuts,lf b u t t h a t on w e l l managed p l a n t a t i o n s an average of 60 n u t s per t r e e could be expected, Cooke (1932) reported t h a t i n well managed p l a n t a t i o n s in Ceylon on good s i t e s where t h e number of

t r e e s per acre was

48

t o 60, y i e l d s of

56

t o 86 nuts per t r e e were ob- t a i n e d and t h a t

15

p i c u l s (0.9 t o n s ) of copra per a c r e were harvested, Child (1950) e s t i m a t e d G t h a t world production of copra i n 1938 was 3,906,11~3 metric tons, produced on about 9,616,000 acres, o r about O , l 6 t o n s per ,acr& ( a metric ton equals 2204,6 pounds), The estimated production i n t h e ItPacific T e r r i t o r i e s " was 0.333 tons per acre.

It is apparent t h a t Arnots per-tree and per-acre productivity i s

1ot.r cor,~pared with t h a t of the world, and even with t h a t of t h e average of t h e "Pacific Territories." This low p r o d u c t i v i t y i s probably i n p a r t due t o i n e f f i c i e n t harvesting, although proba.bly no more than 25 nuts per t r e e could be expected, given t h e crcrrded conditions of the e x i s t i n g groves. Total production of the a t o l l could no doubt be i n - creased by converting soine of t h e ].and under scrub f o r e s t t o coconut

j c Wased on Schnumacher 2s

--

~evicw..oE"~oconut .- Products f o r 193 8,

Ilanila, 1939, Table IVY p022,"

p l a n t a t i o n s , Much of this land, however,

i s

n o t w e l l s u i t e d t o copra production, a s m o s t of

it

c o n s i s t s of boulder ramparts and s t o n y l a n d

. .

exiosed t o wind and s a l t sprayd Assuling t h a t a l l t h i s l a n d be planted . ^,

t o coconuts, t h e acreage under coconut pla&at5.0ns wo&d b e increased

. . . . .

only 25 percent over t h a t of 1952. The gains in copra p r o d u c t i o n t o be

. . . . .

obtained by i n c r e a s e i n acreage o r more e f f i c i e n t harvesting a r e

. .

probably s l i g h t , howev&, compared t o those which might r e s u l t - from more c a r e f u l management than was p r a c t i c e d i n 1952. If t h e groves were

thinned, competing vegetation k e p t nore e f f i c i e n t l y i n check, t h e p r a c t i c e of ap21jing phosphate and perhaps potassium f e r t i l i , z e r s i n i t i a t e d , . and ^. a program of introduction of high-producing races establ.ished, per-acre p r o d u c t i v i t y might w e l l be doubled. The introductr'.on of a vari-ety such a s t h e Philippine Romano would save considerable l a b o r i n making copra, Only3,270 Ronmo n u t s e r e r e q u i r e d t o make one metric ton of copra on Hindanao (ldebster, 1920), whereas about 7,280 n u t s were necessary a t

. . . ..

Arno i n 1952.

. . .. . .

It i s obvious, h&ever9 tljtit prograils designed t o i n c r e a s e copra prodnction a t Arno and elsewhere i n t h e s o u t h e r n Marshalls would r e q u i r e

. ..

changes i n s o c i a l p a t t e r n s which might be undesirable o r unpopular, Although complaints about $he low p r i c e of copra and t h e r e s u l t i n g low income of t h e "rF j e r b a l " were f r e q u e n t i n 1952, it was t h e author's impression t h a t t h e people of Arno were n o t eager t o acquire wealtfi and property. Regdar working hours were unirnorm, To produce enough copra t o buy c i g a r e t t e s , needles, thread, soap, f i s h i n g l i n e , hooks, and o t h e r t r a d e goods t o l a s t h i s i m e d i a t e family one year, a man had only t o work two t o t h r e e weeks a t making copra. Nuch time was s p e n t f i s h i n g , v i s i t i n g , and talking. More e f f i c i e n t management of t h e Arno coconut

groves would possibly double t h e cash income of: the "ri jerbal", b u t on1.y

.. . . . . ^, .

a t the sac-ri:fice of le;.sure hourso Abundant l e i s u r e time i s perhaps one of t h e most pleasant aspects of Marshallese life: Programs t h a t m i & de-

. .

crease

i t

in the name of inc&ased effj.cien&r shou_l.d be reconnnended on1.y

. .

a f t e r c a r e f u l cofisideration has been given t o t h e i r sociological implica+~ionss

. . . . . .

BmpPpuIT TYPE ^{, , ,} .

Primary s p c i e s : Artocarpus a l t i u s (15 t o ³⁰ t r e e s per a c r e ) Secondary species: Cocas' nucifera (10 t o

15.

^. t r e e s . per acre)

Pandanus t e c t o r i u s ' prqnga o b t u s i f o l i a

~ l l o p h y l u s timorensis Pipturus argenteus Guettarda speciosa Norinda o i t r i f o l i a . Ground layera- Wedelia b i f l o r a

Tacca leontopetaloides

..: Lepturus repens

Thuayea involuta.

. , .

. . . ^, . . Fleurya r u d e r a l i s

F i m b r i s t y l i s a t o l l e n s i s Polypodium scolopenrlr5.a Asplenium nidus

. Nephsolepis sp,

.

Y a r a j psts: Cyrtosperma chamissonis Xusa paradisiaca

. . Nibiscus t i l i a c e u s : . .

Colocasia esculenta

, . . . .. .. .. . . Clerodendrum inerlne

Vigna marina ^{. .}

Centella a s i a t i c a _. Ipomoes t u b a .

I. l i t t o r a l i s Oplismenus sp,

Triumfevta procumbens Hedyotis b i f l o r a Alocasia macrorrhiza Crinum a s i a t i c u m . Stenotapl~rum subulatum

A considerable proprotion of the c e n t e r s of t h e wider i s l a n d s was occupied by b r e a d f r u i t f o r e s t s , A coinmon approximate boundary of t h i s type on t h e lagoon s i d e s of i s l a n d s was the main v i l l a g e path p a r a l l e l t o the lagoon, On r e l a t i v e l y narrow i s l a n d s the boundary on t h e ocean s i d e s was o f t e n t h e beginning of the stony land complex or boulder ridge.

On .wider islands, hoveverg t h e b r e a d f r u i t zone u s u a l l y did n o t extend

t h i s f a r , f o r p o t e n t i a l . b r e a d f r u i t l a n d n o t . needed . .. f o r food production

%jas given over,where f e a s i b l e , t o copra culture.

I ^' The breadfruit type was b e s t developed a t Ine, where pigs had n o t been allovred t o run w i l d a n d d e v a s t a t e the y a r a j (Cyrtosperma) p$ts, . .. . a s they had a t A r n o , Bilcarej, and Tutu. . A t Ine these p i t s were about

15

t o 20 f e e t wide, 30 t o 80 f e e t long, and

5

t o 1 0 f e e t deep;:artp heaped . .

up around t h e i r s i d e s formed t h e . s o i l upon which t h e b r e a d f r u i t and.

. .

. p l a n t s associated v i t h i t g r e w . . The b r e a d f r u i t s grew a s widely . . . .

sc'attered t r e e s 50 t o 70 f e e t t a l l , v i t h spreading crorrns 25 t o . ?S,f.eet . . .

in:

diameter, A s t r i k i n g feature. of t h i s type was t h e n e a r l y complete ^{. .} absence of small Wemeter classes. . Breadfruit t r e e s between one and

' e i g h t inches i n diameter wene:def*i-tely. u n c o ~ ~ o n ; most were . 1 8 . t o 36 inches i n diameter above t h e b u t t r e s ~ s , . : , Coconuts were com~on . . i n t h e forest, but occupied .only , a s i n d l proportion of .the ^{. ,} c&opy,. Sprouts of Allophylus, Premna, Guettaraa,

and

i40orinda~pre u s u a l l y abundant along with small b r e a d f r u i t seedlings, and formed secondary f o r e s t s i n abandoned b r e a d f r u i t groves, Openings in +he;canopy permitted rank growths of Wedelia b i f l o r a , the stems of which a t Ine were often i n t e r -

--

laced by ' t h e purple florrered ;owning glory,.

...

^Xpomoea

-

l i t t o r a l i s . _.

In

.

more co~npleiely shaded places t h e grasses Oplismenus, Thuarea, or ^A,,- taphrum covered t h e ground.

In

f a c t , t h e n e a r l y complete ground cover

--

i n both b r e a d f r u i t aild coconut types

--

except where the l a t t e r occwred on stony laiid near t h e . ocean

--

^was

^a

c h a r a c t e r i s t i c of these. a r t i f i c i a l

.! : . f o r e s t s not' shared. by types in which wild n a t i v e t r e e s were predominant,

. .

A t Ine the bottoms of t h e y a r a j p i t s were usually occupied by t h e . : g i g a n t i c Cyl'tospei-ma, b u t . abandoned p.its supported rank growbhs of . ,

Clerodendruin o r t h i c k e t s of Hibiscus t i l i ~ c e u s . , .:,A fresh-water . . . .. . swamp a t Tutu i s l a n d formerly was planted t o yaraj, but since pigs made i t s

c u l t w e . impossible Bruguiera had been .introduced,

.. . . , ^{. . . .} . . . . . . ^.

According t o Fosberg (1?11.9) and Cox ( l 9 5 l ) , ground-water s a l i n i t y

r : . . . .

i s an important f a c t o r c f t h e p h y s i c a l environment ^.. l i m i t i n g t h e d 2 s t r i - bution of t h e b r e a d f r x i t , The typhoon which swept through. t h e e a s t e r n P?a.rsha!ls i n 1.951 provided s t r i k i n g confirmation of t h e s e ideas, A l - though most of Arno a t o l l was r e l a t i v e l y unaffected, t h e b r e a d f r u i t groves of Bikarej were hard-hit, There many t r e e s grer.7 r e l a t i v e l y

. .

c l o s e t o t h e ocean, along t h e majn path which extended in a north-south _{. .} d i r e c t i o n along t h e v e s t s i d e of t h e i s l a n d a KLgh storm waves from t h e _.

,

west washed o v e r t h e land and extended pephaps 200. f e e t i n l a n d a A l l b r e a d f r u i t t r e e s i n t h e path of these waves y e r e icilled o r severely

, . .

damaged, b u t coconuts and c u l t i v a t e d var&eti,es ^{. .} of pardanus were unaffected,

.. .

In 1952 patches of &ad b r e a d f r u i t s a l t e r n a t e d with h e a l t h y bearing t r e e s , so. t h a t it vras s t i l l p o s s i b l e .. . t o detern@ne a t .%rhich ,points ^{. .} and horr far t h e storm waves had washed over t h e land,

Weeds

- -

^{. . :. ,.. .} . ^. .

A g r i c u l t u r a l land throughc~ut much o f t h e t r o p i c s i s characterized

. ,. .

by the presence. of a r e l a t i v e l y unironn weedy f l o r a , These, weeds owe t h e i r present wide d i s t r i b u t i o n s t o t h e agency of man who, w i t h modern, r a p i d methods of t r a n s p o r t a t i o n , has unintentional!.y c a r r i e d sonie of them t o even t h e most remote places, Arno a t o l l i n 1952 had about 26 s p e c i e s of mvanted a l i e n weeds, most of them ~ r i t h o u t rrell e s t a b l i s h e d na.tive names o r usese Most of t h e s e had probably been introchced a f t e r 1873, when an Haiiaiian mLssion tras e s t a b l i s h e d a t Ine, It i s of i n t e r e s t t o observe t h a t on Arno a t o l l t h e s e weeds were v i r t u a l l y r e s t r i c t e d t o v i l l a g e paths and houselots. a t h o u g h t h e b r e a d f r u i t and coconut groves were maintained a s such only by periodic disturbance i n t h e form of

c l e a r i n g and burning underbrush, t h e i r f l o r a s consisted almost exclusively of n a t i v e species o r &&ts of ancierit Aboriginal introduction. Noreover, it

is

a curious f a c t t h a t t h e n a t i v e herbs of coconut. and b r e a d f r u i t f o r e s t , wit11 very f ^&J exceptions, did n o t occur i n t h e f o r e s t s . of w i l d n a t i v e trees. Thus a r i s e s - t h e problem of t h e n a t u r e of t h e i r ancient, pre-aboriginal h a b i t a t s , f o r t h e coconut and b r e a d f r u i t groves, t h e i r present h a b i t a t s , became e s t a b l i s h e d on Arno only a f t e r t h e a r r i v a l of t h e Marshallese,, . ^,

Certain of these s p c i e s ? e r e found in 1952 on open, newly formed land. Betrzeen Langar and &iatol.en, islancls n e a r l y o b l i t e r a t e d in t h e 1905' typhoon were reforining. The follorJing species of herbs trere observed on sand f r e s h l y deposited along t h e lagoon shores of these islands:

Lepturus repens Vigna marina

: ,

' ~ h i b r i s t y l i a - a t o l l e n s i s ^{. .} Wedelia b i f l o r a ,Txiumfetta procumbens ^, . . . Cas sytha f i l i f ornks

. . . .

Since there i s no reason t o believe t h a t typhoons were formerly any l e s s frequent than they a r e nov, it is extremely probable t h a t t h i s h a b i t a t

. has always been available t o t h e s e species. A more extensive search

. . , . . . . . .. . .

would probably r e v e a l a f e v o t h e r species of t h e ground f l o r a of bread-

.

^.

.

^. ,.. ,

. .. .fruit. and coconut groves

--

^e,g., Euphorbia chamissonis and Thuarea _-.- involuta,

--

^growing i n s im il ar s i t u a t i o n s , Certain species which were

. . ,

r e s t r i c t e d t o r e l a t i v e l y moist, p a r t i a l l y shaded s i t u a t i o n s may never

. . have grown on open sandy . . shores. Could such p l a n t s a s Centella ^{$ --}a s i a t i c a Hedyotis b i f l o r a , Ipomoea

---

l i t t o r a l i s , and

-

Gplismenus s p e be weeds of axcient a b o r i g i n a l introduction? .. .. It trou3.d be s u r p r i s i n g lndeed i f such introductions . d i d . n o t take place i n t h e past a s they do today. The

. .;..

seedless v a r i e t i e s of b r e a d f r u i t g f o r example, a r e propagated c h i e f l y

by r o o t suckers. In t r a n s p o r t i n g small t r e e s from i s l a n d t o i s l a n d t h e va.ialrdei"jag ::ars:~a?.lese c o d d e c a r c e l y have avoided accidental i n t r o d u c t i o n

of unwanted seeds in t h e s o t 1 around t h e roots. Other weeds of p o s s i b l e ancient i a t m d u c t i o n a r e Port,ulaca sai?oensis and Cyperus polystachyos _--.-- ---..--

--

^{$. - . - -}

both r e s t r i c t e d t o v i l l a g e paths and houselots, b u t possessing well e s t a b l i s h e d n a t i v e nanes.

. . ^{. .}

SCRUB FOREST

Since t h e jntroduction of t h e copra t r a d e in t h e l a t t e r p a r t of t h e 1 9 t h century, about two t h i r d s of t h e l a n d surface of Arno a t o l l has been c l e a r e d and planted t o coconuts, Probably a t l e a s t 80 percent of t h e 22211 a c r e s of Arno under coconuts i n 195'2 must have suppwted stands of 16ld n a t i v e t r e e s q d shrubs l e s s than LOO years before t h i s study was made.

In 1952 n a t i v e f o r e s t and scrub e x i s t e d c h i e f l y i n t h e form of numerous small stands which f o r t h e most p a r t were r e s t r i c t e d t o s i t u a t i o n s i n which copra production riould probably have been r e l a t i v e l y uneconomic.

1Jal;ive f o r e s t and scrub ms t h u s c h a r a c t e r i s t i c of small o r narrow i s l a n d s remote from v i l l a g e s and of stony l a n d and ramparts, e s p e c i a l l y those exposed t o s a l t spray and t'ne drying e f f e c t of tine n o r t h e a s t t r a d e s , In such s i t u a t i o n s t h e n a t i v e brush acted a s an e f f e c t i v e vind- break, p r o t e c t i n g t h e coconut and b r e a d f r u i t t r e e s planted f a r t h e r inland.

This wild vegetation was com:?osed of wood;. p l a n t s ranging from 2 t o

. .

. . . . . .

80 f e e t in height> and varying i n s t r u c t u r e from n e a r l y ^{. .} impene'crable t h i c k e t s of shrubs along ocean shores t o closed-canopied f o r e s t s of

, , .

l a r g e t r e e s through which one walked pxith ease, Furthemore, t h e type included 1 7 woody species, few of which were d i s t r i b u t e d over t h e e n t i r e

a r e a of the type a s i t i s mapped.

In

vier? of t h e g r e a t range of v a r i a t i o n of physiognomy and f l o r i s t i c composition of t h i s vegetation, it i s perhaps u n r e a l i s t i c t o consider

it

a s i n g l e type. Largely f o r convenience of mapping, however,, t h e scrub f o r e s t i s here t r e a t e d a s a u n i t . It was n o t possible in t h e f i e l d t o examine each of t h e

lb3

stands mapped a s scrub f o r e s t , and i n general . t h e . cor~ponent species cannot be distinguished on a e r i a l photographs of a s c a l e of l e s s than 1 : ~ , 0 0 0 . Subdivision of t h e type based on f l o r i s t i c composition was thus inpracticable. Furthermore,

. .

t h e average s i z e of t h e stands of scrub f o r e s t a s here presented i s only . .

b a c q s ; many of t h e s e a r e 200 f e e t o r l e s s wide. S p l i t t i n g o f t h e type vould have l e d t o obvious d i f f i c u l t i e s i n d r a f t i n g t h e map.

Although t h e scrub f o r e s t of Arno vas reduced i n 1952 t o nmerous small. stands occurring c h i e f l y on the ocean s i d e s of wind~rard islands, i t i s perhaps possible conceptually t o r e c o n s t r u c t t h e appearance of t h e vegetation of t h e a t o l l of t h e e a r l y 1 9 t h century, when perhaps only about

15

percent of t h e land surface of the a t o l l was appropriated f o r agriculture. Certain r e g u l a r i t i e s were observed, f o r example, in t h e d i s t r i b u t i o n s of the n a t i v e t r e e s ^{, :} a s one proceeded across t h e i s l a n d s . , of

. ..

t h e a t o l l from lagoon t o . ocean., . Thus, l a r g e individuals of Pisonia _{. . .}

-.-

^,

grandis occurred on s e v e r a l o f t h e vindward i s l a n d s from Jilang t o Takleb.

r . . .,

It is p r o b a b l e t h a t these t r e e s were r e l i c s o f former f o r e s t s i n whbh Pisonia was an important species. In 1952 Pisonia a l s o formed f o r e s t s along t h e boulder ramparts of a ferr islands, but t h e t r e e s were much s . d l e r than t h e s c a t t e r e d individuals s t i l l standing inland. Gn t h e b a s i s of such observations

it

i s possible t o construct a diagram (Fig. 12) on which a r e charted the d i s t r i b u t i o n s of t h e more important species of