The coastal sand vegetation of Peninsular Thailand can be divided in to: 1. Sandbar vegetation caused by sedimentation from sea currents and include dune grassland, dune scrub and dune woodland, and 2. Sandbar vegetation caused by strong wind which include dune grassland and dune scrub (Laongpol et al. 2009).

Sandbar vegetation caused by sedimentation from sea current

East Coast
Natural sandbar vegetation on the east coast is thought to have extended from north of Chumphon throughout much of peninsular Malaysia. However, much has now been lost. Only fragmented remnants are left such as at “Chaiya sandbar” in Surat Thani. In Chaiya district, quite a few remnants of natural sandbar vegetation can be seen in fragmented patches along the Chaiya sandy coast from Ban Takrop to Ban Nuea.

Here the dune grassland typically includes Canavalia rosea, Chrysopogon orientalis, Ipomoea imperati, Ipomoea pes-caprae, Ischaemum muticum, Remirea maritima, Sesuvium portulacastrum, Spinifex littoreus, Vigna marina, Vitex rotundifolia and Zoysia matrella.

The dune scrublands charateristically comprise stunted, shrubby tree up to 8 m high. These include Acronychia pedunculata, Chaetocarpus castanocarpus, Eurycoma longifolia, Lannea coromendelica, Olea brachiata, Pouteria obovata, Rapanea porteriana, Syzygium gratum and Vatica harmandiana. Among the shrub species are Atalantia monophylla, Breynia racemosa, Catunaregam tomentosa, Melastoma malabathricum, Micromelum minutum, Rhodomyrtus tomentosa, Salacia chinensis and Suregada multiflorum. The ground layer may comprise Dianella ensifolia, Wikstroemia ridleyi, orchids such as Doritis pulcherrima, ferns like Davallia denticulata and Drynaria sparsisora. Vines such as Cansjera rheedei, Dischidia major, Hoya parasitica and Psychotria sarmentosa may also be present but these tend to be scattered.

Dune woodland in the innermost zones typically has a three storey vertical structure. The canopy up to 18 m high mainly comprises Shorea roxburghii. The middle layer, which ranges from 10–12 m, mainly comprises Vatica harmandiana and Vitex pinnata. Shrubs and saplings make up much of the undergrowth with species such as Ardisia crenata, Carallia brachiata, Champereia manillana, Eurycoma longiflia, Ixora javanica, Microcos tomentosa, Micromelum minutum, Ochna integerrima, Olea brachiata, Pouteria obovata and Rapanea porteriana. The climbers include Ancistrocladus tectorius, Cansjera rheedei, Dischidia major, Hoya parasitica, Psychotria sarmentosa and Tetracera indica. The ground layer commonly includes ferns such as Davallia denticulata and Drynaria sparsisora, and herbs such as Dianella ensifolia. However, the species composition of these woodlands varies from place to place. At Ban Nuea the upper storey reaches heights of up to 30 m and consists of Dipterocarpus alatus and D. chartaceus. The lower layer (15–20 m) mainly includes Mangifera indica and Shorea roxburghii. The undergrowth, somewhat disturbed by human activities, still supports native species such as Ardisia crenata, Champereia manillana, Eurycoma longifolia, Memecylon ovatum, Morinda elliptica and Ochna integerrima.

West Coast
Much of the west coast vegetation has developed on narrow sandbars in small fragmented stands but almost all of the natural vegetation has been reduced or modified mainly due to the impact of tourism. However, there are a few remnants of natural sandbar vegetation left in some protected areas such as Khao Lampi-Hat Thai Mueang National Park, Thung Thale non-hunting areas and Hat Chao Mai National Park. The remnant patches at Hat Thai Mueang are fairly represenative of west vegetation but some was destroyed by the ‘tsunami’ tidal waves of 2005. Here the outer dune scrub zone comprises Atalantia monophylla, Calophyllum pulcherrimum, Crinum northianum, Diospyros areolata, D. ferrea, Hydrophylax maritima, Ischaemum muticum, Pandanus odoratissimus, Pouteria obovat, Rhodomyrtus tomentosa and Scaevola taccada. The inner scrub zone is mainly formed by species characteristic of west coast sandbars, but it tends to be scattered and often divided by small patches of other plant communities. Each stand is mainly composed of a shrubby tree species such as Cotylelobium lanceolatum and Rapania porteriana surrounded by other shrubs or treelets such as Rhodamnia cinerea, Rhodomyrtus tomentosa, Styphelia malayana and Syzygium gratum, while the ground layer typically includes orchids such as Doritis pulcherrima, Dendrobium crumenatum, Dendrobium indivisum and Dendrobium pachyphyllum.

The dune woodland develops as a continual narrow strip and usually charactrized by three storeys. The canopy at 15–18 m is dominated by dipterocarp species such as Shorea roxburghii. The lower layer at 8–10 m comprises smaller trees and shrubs such as Acronychia pedunculata, Pouteria obovata, Syzygium gratum and Vatica harmandiana. Typical undergrowth species are Calophyllum pulcherimum, Rhodamnia cinerea and Rhodomyrtus tomentosa and ferns such as Davallia denticulata, D. heterophylla, D. pectinata, Drynaria sparsisora, Pyrrosia piloselloides, Schizaea dichotoma and S. digitata are common. However, species composition varies from place to place.

Sandbar vegetation caused by wind storms

Only one site at Ban Bangboet, Pathio district, Chumphon, in the northernmost part of the peninsula is recognized and this is regarded as unique on the plain of the eastern coast of peninsular Thailand. Much of the vegetation is affected by strong winds but can develop quickly when a level of stability is achieved. The dune grassland includes Cyperus stoloniferus, Fimbristylis sericea, Ipomoea imperati and Ipomoea pes-caprae. Among the dune scrub species are shrubby trees and shrubs such as Ardisia crenata, Calophyllum pulcherimum, Diospyros ferrea, Eurycoma longifolia, Pandanus odoratissimus, Pouteria obovata, Sindora siamensis, Scaevola taccada and Syzygium gratum. Climbers and herbs typically include Dunbaria bella, Dianella ensifolia and Tetracera indica.


Laongpol, C., Suzuki, K., Katzensteiner, K. & Sridith, K. 2009. Plant community structure of the coastal vegetation of peninsular Thailand. Thai Forest Bulletin (Botany), Special Issue: 106–133.