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2. Littoral Shrubland 'I'his is the native shrubby vegetation typically occurring inland of the herbaceous strand (when prcscnt) and seaward of the littoral forest. It is same community recognized on Ta'u (Whistler 1992b). Like herbaceous strand, it may occur on either rocky, sandy, or coral rubble shores. However, it most commonly occurs on rocky coasts, and often blends into the herbaceous strand on this sub-strate, especially when the shrubs are dwarfed by prevailing sea winds. Littoral shrubs are typically intolerant of shade, and do not extend into the forest, where different shrubs, saplings, and ferns dominate. Within the park boundaries areas of littoral shrubland occur primarily where rocky points slope into the sea rather than forming cliff-bound headlands. Only a few examples of this community exist within the park boundaries, at least in areas that are accessible; the best examples on Tutuila are on the lhfuna coast on the north-central part of the island bctwcen Fogagogo and Vaitogi, where the lava- bound coast forms a suitable habitat for the shrubs. The best examples in American Samoa are on the southern tip of Olosega, and on the south corners of Ta'u. The most typical littoral shrubland species in Samoa are Scaevola taccada (to'ito'i) and Wollastonia biflora (beach sunflower, ateate). Scaevola is a shrub that is widespread in the Pacific. Wollastonia, a species with a similarly wide distribution, is more of a subshrub in most areas, app- earing even vinelike when it hangs down from cliffs of headlands. Other typical species in this habitat arc Clcrodendrum inerme (aloalo tai), Colubrina u.viutica (fisoa), Dendrolobium umbellatum (lala), and C'yrtandra samoensis. The best accessible area of littoral shrubland within the park is found on the precipitous slopes of Polauta Ridge at the north end of Vatia beach (Fig. 13). An equally good example is Pola Islet (Fig. 14), but this in inaccessible. The vegetation on the islet and on the cliffs of the ridge is actually a mixture of littoral herbs, shrubs, and trees that find a tenacious existence on the cliffs and in rock cracks. Because the littoral plants present are not trees, the vegetation cannot be classed as littoral forest. But since most of the species on Pola Islet are woody, it is probably most accurate to consider the whole plant cover as littoral shrubland. The dominant species present here is Scaevola taccada. Other common woody species present are Clerodendrum inerme, Premna serratifolia, Hibi- scus tiliaceus, Morinda citrifolia, and Pisonia grandis. The most abundant herbs are the grasses Lepturus repens and Stenotaphrum micranthum, and the fern Acrostichum aureum. Higher up the slopes the fern Davallia solida forms dense patches, probably in cracks and on ledges. A different kind of littoral shrubland is present at the north end of Vatia on the flat coral rubble bench above the sloping beach. This is dominated by Hibiscus tiliaceus, but also common here are Clerodendrum inerme, Barringtonia asiatica, Morinda citrifolia, and Ficus scabra. This may actually be the remains, and beginnings, of a littoral forest that was cut down or destroyed by hurricanes. A similar vegetation covers the talus slopes behind this area, and may be a disclimax vegetation kept from reverting to littoral forest by the talus that slides or falls down from the adjacent cliffs. Another variation of littoral shrubland sometimes mentioned in the literature is one dominated by Pandanus tectorius (screwpine, fasa). While there are areas on Tutuila where this tree-like monocot forms monodominant stands, such as on the Tafuna coast between Fogagogo and Vaitogi, the plant is uncommon within the park boundaries. It fact, Pandanus was not even noted during the survey as occurring on any of the beaches visited (it was, however, seen at higher elevations on Mauga-o- Tula). Consequently, the possible distinctiveness of Pandanus scrub vegetation is a moot point within the park boundaries. 3. Littoral Forest This is the forest that occurs directly on the shore (or just inland of the other zones of littoral vegetation) and is dominated by trees that owe their distribution either directly or indirectly to the effects of the sea. It is the same community recognized on Ta'u (Whistler 1992b). It ofien occupies a narrow zone sometimes only 50 or 100 m in width, especially on level coasts where it is replaced inland by lowland forest. This was the case in Amalau before it was disturbed; here the disturbed littoral forest zone is replaced inland by secondary forest
Figure 14. Littoral shrubland vegetation on Pola Islet. Figure 15. Aiga Bay, west of and outside of the Tutuila park. 17
Page 1 and 2: COOPERATIVE NATIONAL PARK RESOURCES
Page 3 and 4: TABLE OF CONTENTS I . INTRODUCTION
Page 5 and 6: LEGEND B \ PROPOSED PARK AREA OFU I
Page 7 and 8: Figure 3 VEGETATION TYPE MAP Tutuil
Page 9 and 10: Figure 4. Pago Pago Bay, with Mt. M
Page 11 and 12: 'IJpolu, and 'Ta'u as well). The on
Page 13 and 14: nu pucijicuJ; an Eurya? [Eurya pick
Page 15 and 16: category recognized in the report o
Page 17 and 18: Figure 10. Tuafanua Beach west of V
Page 19: Figure 12. Littoral shrubland veget
Page 23 and 24: Figure 16. Littoral forest north of
Page 25 and 26: Soils differ in origin and age of t
Page 27 and 28: example on Tutuila is the climbing
Page 29 and 30: When undisturbed, the floor of the
Page 31 and 32: incrme (aloalo tai) may also be com
Page 34 and 35: coastal ridges, decreases in import
Page 36 and 37: Scvcral other trees are characteris
Page 38 and 39: poIvon/l~os, Dtrvulliu solidu (whic
Page 40 and 41: Although Mauga-o-Tula lacks some of
Page 42 and 43: introduced weeds, many of the Polyn
Page 44 and 45: even mature secondary forest, it le
Page 46 and 47: there). No increased access should
Page 48 and 49: Whistler, W. A. 1976. Wetlands of A
Page 50 and 51: Acrostichum aureum L. [swamp fern]
Page 52 and 53: Uncommon in montane to cloud forest
Page 54 and 55: 171 ; Setchell 393; Christophersen
Page 56 and 57: of the costa. Uncommon in montane t
Page 58 and 59: liom China to I'itcairn Island. USE
Page 60 and 61: lamina deeply cut into 1-10 lobes,
Page 62 and 63: Antrophyum alatum Bracken. VITTARIA
Page 64 and 65: weed in villages and along roadside
Page 66 and 67: 650 111 clevi~tion. A modern introd
Page 68 and 69: Vernonia cinerea (L.) Less. [ironwe
Page 70 and 71:
Uncomnion in secondary forest, prob
Page 72 and 73:
from near sea level to 400 m elevat
Page 74 and 75:
*Charnaesyce prostrata (Ait.) Small
Page 76 and 77:
elevation. A modern introduction, n
Page 78 and 79:
Macroptilium lathyroides (L.) Urb.
Page 80 and 81:
Cyrtandra samoensis A. Gray momolea
Page 82 and 83:
'Thespesia populnea (L.) Sol. ex Co
Page 84 and 85:
Ficus prolixa Forst. f. [banyan] ao
Page 86 and 87:
found in Tonga, Futuna, and Fiji. S
Page 88 and 89:
Peperomia pellucida (L,.) Kunth POL
Page 90 and 91:
*Gardenia taitensis DC. "Hedyotis c
Page 92 and 93:
elevation. This species should be t
Page 94 and 95:
"Physalis angulata L. 1 wild cape g
Page 96 and 97:
*Etatosterna scabriusculum Setchell
Page 98 and 99:
Epipremnum pinnaturn (L.) Engl. Ili
Page 100 and 101:
Mariscus secmannianus (Boeck.) Pall
Page 102 and 103:
*Bulbophyllurn samoanum Schlechter
Page 104 and 105:
Malaxis resupinata (Forst. f.) Kunt
Page 106 and 107:
F. homhronii Mart.; it differs from
Page 108 and 109:
this in D. ciliaris, but the two ha
Page 110 and 111:
Paspalurn orbiculare Forst. f. Mcdi
Page 112 and 113:
APPENDIX B: PLOT DATA (Basal area i
Page 114 and 115:
PLOT 4: MULIULU LOWLAND RIDGE FORES
Page 116 and 117:
PLOT 6: TIATAUALA LOWLAND RIDGE FOR
Page 118 and 119:
PLOT 8: OLO LOWLAND RIDGE FOREST (2
Page 120 and 121:
PLOT 10: AMALAU LOWLAND VALLEY FORE
Page 122 and 123:
PLOT 12: ALAVA MONTANE FOREST* (400
Page 124 and 125:
APPENDIX C: SEASONALITY OF IMPORTAN
Page 126 and 127:
MORACEAE Ikus godcfl'royi 1;icus ob
Page 128 and 129:
SPECIES FAMILY FLOWERING DATES FRUI
Page 130 and 131:
2. Littoral Shrubland Two types of
Page 132 and 133:
the relatively undisturbed places,
Page 134 and 135:
harvcyana (laupata), Morinda citrif
Page 136 and 137:
APPENDIX F. SUMMARY OF THE VASCULAR
Page 138 and 139:
VIlTAKIACEAE Amrophyurn alaturn Ant
Page 140 and 141:
Species FAMILY Status* E I P M ....
Page 142 and 143:
MYRSINACEAE Embelia vaupelii Maesa
Page 144 and 145:
Species FAMILY Status* E I P M VEKB
Page 146:
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