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== Vernacular names ==
*Terap
== Properties ==
Terap and keledang are not well separated and show much overlap. The arbitrary limit is at a density of 640 kg/m<sup>3</sup>at 15% moisture content and the heartwood of keledang is moreover darker and more clearly defined from the sapwood than terap.
Terap is a lightweight hardwood. The heartwood is yellow to pale yellow-brown and usually indistinctly demarcated from the paler sapwood. The density is (310-)365-640(-780) kg/m<sup>3</sup>at 15% moisture content. The grain is interlocked, texture coarse but even.
At 15% moisture content, the modulus of rupture is 36-68 N/mm<sup>2</sup>, modulus of elasticity 7410-12 000 N/mm<sup>2</sup>, compression parallel to grain 27-35 N/mm<sup>2</sup>, compression perpendicular to grain 3 N/mm<sup>2</sup>, shear 5-9 N/mm<sup>2</sup>, cleavage 32 N/mm radial and 36 N/mm tangential, Janka side hardness 2070-2650 N and Janka end hardness 3760 N.
Terap is easy to work. It can be sawn, planed, bored and turned easily, but the quality of finish is often rough, especially on radial surfaces due to grain picking up because of the interlocked grain. It can be peeled satisfactorily and is suitable for plywood production, having good gluability.
Terap is classified as non-durable under tropical conditions when exposed to the weather or in contact with the ground (with a service life of 1-1.5 years). The sapwood absorbs preservatives easily, but the heartwood is moderately difficult to treat, with an absorption of about 75 kg/m<sup>3</sup>of creosote using an open tank treatment. A retention of 12.5 kg/m<sup>3</sup>has been reported in Indonesia for ''A. kemando'' wood using CCA preservative.
Terap wood contains 59-71% holocellulose, 41-45%α-cellulose, 22.5-27.5% lignin, 13-14% pentosan and 0.6-1.4% ash. The solubility is 2.5-6.4% in alcohol-benzene, 1.5-6.2% in hot water and 11.6-16.9% in a 1% NaOH solution.
Keledang is a medium-weight hardwood. The heartwood is orange yellowish-brown, sometimes with an olive-green tinge, generally darkening considerably on exposure and usually well defined from the paler sapwood. The density is (420-)640-875(-945) kg/m<sup>3</sup>at 15% moisture content. The density of the wood of the well-known fruit trees ''A. altilis'', ''A. heterophyllus'', ''A. integer'' and ''A. odoratissimus'' is 505-645 kg/m<sup>3</sup>, 420-710 kg/m<sup>3</sup>, 545-790 kg/m<sup>3</sup>and 580-780 kg/m<sup>3</sup>respectively at 15% moisture content. The grain is often deeply interlocked, texture moderately coarse and even.
At 15% moisture content, the modulus of rupture is 53-107 N/mm<sup>2</sup>, modulus of elasticity 8700-15 500 N/mm<sup>2</sup>, compression parallel to grain 45-65 N/mm<sup>2</sup>, compression perpendicular to grain 5-10 N/mm<sup>2</sup>, shear 9.5-12.5 N/mm<sup>2</sup>, cleavage 45 N/mm radial and 47.5 N/mm tangential, Janka side hardness 4865-5830 N and Janka end hardness 5780-7560 N.
Keledang is often difficult to saw; saw teeth are severely blunted. This is probably partly a result of the presence of tension wood, and sometimes a result of the presence of silica. The wood can be planed to a smooth surface, but there is some picking up on radial surfaces, boring is moderately easy to difficult and turning is easy. The nailing properties are good. Keledang is of less value than terap for the production of plywood because of its higher density.
Keledang is non-durable to moderately durable; the average service life in contact with the ground under tropical conditions varies between the species from 1.2-3.3 years. The wood is generallycomparatively generally comparatively resistant to termite attack but it is more susceptible to powder-post beetle attack. Wood of ''A. lanceifolius'' showed some resistance to marine borers. The heartwood is very difficult to impregnate, absorbing only about 16 kg/m<sup>3</sup>of preservative using an open tank process.
Keledang wood contains 63-71% holocellulose, 40-44%α-cellulose, 16-25% lignin, 13-14% pentosan and 0.3-1.9% ash. The solubility is 4.6-9.6% in alcohol-benzene, 5.9-13.3% in hot water and 15.6-23.1% in a 1% NaOH solution.
== Wood anatomy ==
*Heartwood yellow to yellowish-brown or golden brown, often turning darker upon exposure, usually distinctly demarcated from the sapwood in keledang but not in terap. *Grain interlocked. *Texture coarse. *Growth rings indistinct, with sporadic short and fine light-coloured bands; yellowish or whitish chalky substance occasionally present in vessels and orange-coloured substance in ray cells and axial parenchyma, often visible with hand lens, yellowish-brown fine streaks sometimes visible with hand lens in rays on the radial surface.
*Growth rings usually indistinct, but when present generally marked by long wings of parenchyma and smaller pores.
