6238

5(3): Timber trees; Lesser-known timbers

Sarcotheca Blume

Mus. bot. 1: 241 (1850).

OXALIDACEAE

x = unknown; 2n = unknown

Brunei: tebarus. Indonesia: pupoi (Sumatra). Malaysia: belimbing pipit, pupoi, setundok (Peninsular).

Sarcotheca comprises 11 species occurring in Peninsular Malaysia, Sumatra, Borneo and Sulawesi.

The wood of Sarcotheca is used for roofing and interior work.
The sour fruits are eaten in curries and cooked with vegetables and sweets, and are said to be a remedy against cough.

Sarcotheca wood is used rarely and on a local scale only.

Sarcotheca yields a medium-weight hardwood with a density of 650-840 kg/m³ at 15% moisture content. Heartwood pale straw-coloured or brownish, not clearly differentiated from the sapwood; grain straight; texture rather fine and even. Growth rings sometimes distinct, boundaries indicated by narrow zones of denser tissue and usually a narrow layer of apparently marginal parenchyma; vessels very small to medium-sized, solitary and in radial multiples of 2-8, all vessel sizes found in the multiples, open and with tyloses; parenchyma sparse, mainly apotracheal, with apparently narrow marginal bands (septate fibres with crystals), just visible to the naked eye, and diffuse, and paratracheal vasicentric, the latter type indistinct even with a hand lens; rays very fine; ripple marks absent.
The wood is moderately hard, fairly strong and easy to work. It is slightly to moderately durable.
See also the table on microscopic wood anatomy.

Shrubs or small to medium-sized or fairly large trees up to 42 m tall; bole up to 100 cm in diameter, deeply fluted, sometimes with buttresses up to 2(-4) m high; bark surface smooth to scaly or dippled, reddish to reddish-brown, inner bark fibrous, yellow-brown to light red or pink. Leaves alternate, 1- or 3-foliolate, exstipulate; leaflets entire; petiole jointed, its apex and the petiolules swollen and wrinkled. Inflorescence axillary or terminal, solitary or few together, composed of cymes arranged along a simple or sparsely branched rachis. Flowers heterodistylous, 5-merous; sepals unequal, connate at base; petals contorted, free at base but adhering above the claw and falling jointly; stamens 10, connate at base, longer and shorter ones alternating; ovary superior, 5-locular with 2 ovules in each cell, styles free. Fruit a fleshy, red or black, 5-lobed berry, with persistent sepals. Seed flat, without aril; testa reddish. Seedling with epigeal germination; cotyledons emergent, leafy; hypocotyl elongated; first 2 leaves opposite, subsequent ones alternate. In S. griffithii the first few leaves are 1-foliolate, later ones 3-foliolate.
Growth is in flushes; the stem of saplings zigzags between the nodes. Young leaves are deep violet. Pollination is by insects (e.g. Xylocopa bees) and cross-pollination is favoured by the heterodistylous flowers; flowers are long- or short-styled. Flowering and fruiting are almost throughout the year, but S. celebica flowers from January to April. In S. celebica pollination only succeeded when pollen of short-styled trees was brought on stigmas of long-styled ones; seed set was comparatively poor. The flowering-to-fruiting period of S. griffithii in Peninsular Malaysia is about 16 weeks. The fruits are eaten by bats, birds and monkeys which thus disperse the seeds.
The woody genera presently included in the Oxalidaceae used to be in the families Averrhoaceae and Lepidobotryaceae which were even assigned to different orders. More recent investigations, however, retain a broader concept of the Oxalidaceae. In the field Sarcotheca can be confused with Rourea, but the latter has free carpels, seeds with an aril, and dry, 1-celled and 1-seeded fruits.

Sarcotheca is found scattered in primary or secondary, lowland rain forest, up to 900 m altitude.

Sarcotheca can be propagated by seed. Seeds of S. griffithii show about 45% germination in 10-25 days. In a 50-ha plot in lowland forest in Peninsular Malaysia, there were 209 specimens of S. griffithii and 179 of S. monophylla with stems over 1 cm in diameter, of which 47 and 31 stems respectively measured over 30 cm in diameter.

As Sarcotheca is not commercially exploited the risk of genetic erosion is low.

It is unlikely that Sarcotheca timber will be used increasingly in the near future.

[163]Burkill, I.H., 1966. A dictionary of the economic products of the Malay Peninsula. 2nd edition. Ministry of Agriculture and Co-operatives, Kuala Lumpur. Vol. 1 (A-H) pp. 1-1240. Vol. 2 (I-Z) pp. 1241-2444.
[198]Cockburn, P.F., 1976-1980. Trees of Sabah. 2 volumes. Sabah Forest Records No 10. Forest Department Sabah, Sandakan.
[267]Desch, H.E., 1941-1954. Manual of Malayan timbers. Malayan Forest Records No 15. 2 volumes. Malaya Publishing House Ltd., Singapore. 762 pp.
[341]Flora Malesiana (various editors), 1950-. Kluwer Academic Publishers, Dordrecht, Boston, London.
[436]Heyne, K., 1927. De nuttige planten van Nederlands-Indië [The useful plants of the Dutch East Indies]. 2nd edition, 3 volumes. Departement van Landbouw, Nijverheid en Handel in Nederlandsch-Indië. 1953 pp. (3rd edition, 1950. van Hoeve, 's-Gravenhage/Bandung. 1660 pp.).
[458]Hutchinson, J., 1967. The genera of flowering plants. Vol. 2. The Clarendon Press, Oxford. 659 pp.
[464]Ilic, J., 1990. The CSIRO macro key for hardwood identification. CSIRO, Highett. 125 pp.
[553]Kessler, P.J.A. & Sidiyasa, K., 1994. Trees of the Balikpapan-Samarinda area, East Kalimantan, Indonesia. Tropenbos Series 7. The Tropenbos Foundation, Wageningen. 446 pp.
[646]Lack, A.J. & Kevan, P.G., 1987. The reproductive biology of a distylous tree, Sarcotheca celebica (Oxalidaceae) in Sulawesi, Indonesia. Botanical Journal of the Linnean Society 95: 1-8.
[800]Mohd Ghazali, H.O. & Abd. Rahim, A. S., 1985. Flowering-to-fruiting period of Malaysian forest trees. Malaysian Forester 48: 254-257.
[829]Ng, F.S.P., 1991-1992. Manual of forest fruits, seeds and seedlings. 2 volumes. Malayan Forest Record No 34. Forest Research Institute Malaysia, Kepong. 997 pp.
[831]Ng, F.S.P. & Mat Asri Ngah Sanah, 1991. Germination and seedling records. Research Pamphlet No 108. Forest Research Institute Malaysia, Kepong. 191 pp.
[861]Oey Djoen Seng, 1951. De soortelijke gewichten van Indonesische houtsoorten en hun betekenis voor de praktijk [Specific gravity of Indonesian woods and its significance for practical use]. Rapport No 46. Bosbouwproefstation, Bogor. 183 pp.
[1048]Soepadmo, E., Wong, K.M. & Saw, L.G. (Editors), 1995-. Tree flora of Sabah and Sarawak. Sabah Forestry Department, Forest Research Institute Malaysia and Sarawak Forestry Department, Kepong.
[1158]Veldkamp, J.F., 1967. A revision of Sarcotheca Bl. and Dapania Korth. (Oxalidaceae). Blumea 15: 519-543.
[1164]Verheij, E.W.M. & Coronel, R.E. (Editors), 1991. Plant resources of South-East Asia No 2. Edible fruits and nuts. Pudoc, Wageningen. 446 pp.
[1221]Whitmore, T.C. & Ng, F.S.P. (Editors), 1972-1989. Tree flora of Malaya. A manual for foresters. 4 volumes. Malayan Forest Records No 26. Longman Malaysia Sdn. Berhad, Kuala Lumpur & Petaling Jaya.
[1242]Wong, T.M., 1982. A dictionary of Malaysian timbers. Malayan Forest Records No 30. Forest Research Institute Malaysia, Kepong. 259 pp.

R.C.K. Chung

Sarcotheca celebica
Sarcotheca diversifolia
Sarcotheca griffithii
Sarcotheca monophylla

Chung, R.C.K., 1998. Sarcotheca Blume. In: Sosef, M.S.M., Hong, L.T. and Prawirohatmodjo, S. (Editors): Plant Resources of South-East Asia No 5(3): Timber trees; Lesser-known timbers. PROSEA Foundation, Bogor, Indonesia. Database record: prota4u.org/prosea

The following species in this genus are important in this commodity group and are treated separatedly in this database:
Sarcotheca celebica
Sarcotheca diversifolia
Sarcotheca griffithii
Sarcotheca monophylla