Dipterocarpus

Content

Description

Medium-sized to large trees with thick, rounded, usually small and concave, sometimes tall and straight buttresses. Bark surface pale or dark grey to orange-brown, sometimes pink-brown; Leaves coriaceous, rarely thin, margin usually sinuate towards the apex; Stipules large, hastate to lorate, obtuse, +- succulent, caducous, characteristically carpeting the forest floor in the growing season. Inflorescence racemose, short, stout, zig-zag, few-flowered, somewhat irregularly sparingly branched; Flowers large. . Petals large, narrowly oblong, strongly contorted, loosely cohering at base on falling, cream with a prominent pink stripe down the centre. Stamens 15-40, persisting at first in a ring round the ovary after the petals fall; Ovary enclosed in the calyx tube, the apex ovoid to conical, shortly tomentose; Fruit large. .

Distribution

Asia-Temperate: China South-Central (Yunnan present), Asia-Tropical: Borneo present; India present; Jawa (Jawa present); Lesser Sunda Is. (Bali present); Malaya present; Sumatera (Sumatera present); Thailand (Thailand present), Burma present, Ceylon present, E. Africa, Philippines and intervening islands present, Sumbawa present

About 69 spp., in Ceylon, India, Burma, Thailand, Indochina, and Yunnan and 53 or 54 species in Malaya, Sumatra, Java, Bali, Sumbawa, Borneo, Philippines and intervening islands. Fossil records from the Tertiary in E. Africa. .

Anatomy

One of the most clearly defined genera in the family; twigs with many resin canals, in 1-2 concentric rings, in the outer margin of the pith; leaf traces 3, arising in the distal 1/2 of each internode with 12 stipule traces; distal end of petiole with 1-3 semicircles of vascular bundles, each with a resin canal, closed by an adaxial bar of collateral vascular tissue.

Taxonomy

The genus has since Dyer (1874a) habitually been divided into five sections on the basis of the fruit calyx tube; Sphaerales (tube round in cross-section); Tuberculati (with 5 distal tubercles); Angulati (5-angled); Alati (5-winged) and Plicati (5-winged with the wings proliferated into folds thus obscuring the tube). These characters are not only uncorrected with others, and thus do not appear to define natural groupings, but are inconsistent even within single species. Thus for example the winged fruit calyx tube of D. zeylanicus Thw. is frequently angled, even smooth; the tuberculate fruit of D. costulatus and D. kunstleri are sometimes distally winged; the angled fruit of D. globosus is sometimes merely obscurely tuberculate and the narrowly winged fruit of D. fagineus is sometimes hardly more than angled, while the wings of that of D. sublamellatus are partially folded and place it in an intermediate position between Alati and Plicati. These sections are not therefore adopted in this account (cf. ).

Uses

Light to medium timbers absorbing preservatives readily; used for railway sleepers and heavy construction. The oleoresin is tapped in the semi-evergreen forests of Indochina and Burma, and sometimes elsewhere, for varnishes and tallow, by cutting into the bole and wounding the tissues by burning.

Notes

Following Rec. 75A of the Code I have treated the generic name as masculine, and not as feminine as van Slooten did.

Citation

Smitinand 1958 – In: Thai For. Bull.: 1

Foxw. 1932 – In: Mal. For. Rec.: 56

Sym. 1943 – In: Mal. For. Rec.: 153

Ashton 1963 – In: Gard. Bull. Sing.: 233

Meijer & Wood 1964 – In: Sabah For. Rec.: 230

Gaertn.f. 1968: Man. Dipt. Brunei: 6

Sloot. 1927 – In: Bull. Jard. Bot. Btzg: 263

Burk. 1935: Dict.: 838

Gilg 1925 – In: E. & P., Pfl. Fam., ed. 2, 21: 250

Gaertn.f. 1874 – In: J. Bot.: 149

Wall. 1828: Cat.: n. 953

Gaertn.f. 1978 – In: Gard. Bull. Sing.: 5

Gaertn.f.: 101, 152. – In: J. Bot.: t. 143-145

Heyne 1927: Nutt. Pl., ed. 2: 1093

Backer & Bakh.f. 1963 – In: Fl. Java: 328

Parker 1931 – In: Ind. For. Rec.: 1

Vesque 1874 – In: C. R. Ac. Sc. Paris: 625

Dyer 1874 – In: Fl. Br. Ind.: 294

Burck 1887 – In: Ann. Jard. Bot. Btzg: 194

L. G. den Berger 1926: Hand. Ned. Ind. Natuurwet. Congr. Batavia: 400

Ashton 1964: Man. Dipt. Brunei: 16

Brandis 1895 – In: J. Linn. Soc. Bot.: 24

Heim 1892: Rech. Dipt.: 24

Browne 1955: For. Trees Sarawak & Brunei: 102

Endl. 1840: Gen. Pl.: 1013

Smitinand 1980 – In: Thai For. Bull. (Bot.): 24

Bl. 1825: Bijdr.: 223

Gaertn.f. 1938 – In: Philip. J. Sc.: 245

DC. 1868 – In: Prod.: 610