Alstonia spp.
Family: Apocynaceae
Pulai
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Other Common Names: Milkwood (Papua New Guinea), Dita (Philippines), Shaitan wood (India), Mo Cua (Vietnam), Basong (Malaya), Mergalang (Sarawak), Milky pine, White cheesewood (Australia).

 

Distribution: Throughout the Indo-Malayan region, Australia, and Polynesia.  Varying with species, found on dry land and swampy sites.

 

The Tree: Clear straight boles 40 to 50 ft in length, sometimes reaching 90 ft; diameters commonly 3 to 4 ft.  Stems are characteristically fluted; sometimes buttressed.

 

The Wood:

General Characteristics: Sapwood yellowish white to pale brown; not differentiated from heartwood; texture moderately fine to somewhat coarse; grain mostly straight, sometimes interlocked; quite lustrous; without characteristic odor or taste when dry. Has large slit-like latex canals.

 

Weight: Basic specific gravity (ovendry weight/green volume) 0.34 to 0.40; air- dry density 25 to 30 pcf.

 

Mechanical Properties: (2-in.  standard)

 

Moisture content   Bending strength   Modulus of elasticity   Maximum crushing strength

            (%)                  (Psi)                            (1,000 psi)                   (Psi)

Green (9)                     5,130                           900                              2,790

6%                               7,480                           1,060                           4,560

 

Green (34)                   5,800                           960                              3,120

 

Janka side hardness 380 lb for green material and 460 lb for dry.  Green Forest Products Laboratory toughness 179 in.-lb (5/8-in.  specimen).

 

Drying and Shrinkage: The wood is reported to be easy to air dry with little or no degrade.  Kiln schedule T10-D4S is suggested for 4/4 stock.  Shrinkage green to overdry: radial 3.4%; tangential 6.1%.

 

Working Properties: Very easy to work by hand and machine tools; cuts smoothly; turns well.  Peels easily on a rotary lathe.  Nails well.

 

Durability: Prone to stain, decay, and insect attack.  Very susceptible to attack by powder-post beetles.

 

Preservation: At least one species is reported to absorb preservatives very readily.

 

Uses: Patternmaking, boxes and crates, carving, veneer and plywood, interior trim, furniture components.  Root wood of A. spathulata once used for "pith" helmets.

 

Additional Reading: (9), (12), (34), (47)

 

9. Burgess, P. F. 1966.  Timbers of Sabah.  Sabah For.  Rec.  No.  6.

12.  Douay, J. 1956.  Gmelina arborea (Roxb.).  Monographie Bois For.  Trop.  48:25 38.

34.  Lauricio, F. M., and S. B. Bellosillo.  1966.  The mechanical and related properties of Philippine woods.  The Lumberman 12(5):66 +A-H.

47.  Pearson, R. S., and H. P. Brown.  1932.  Commercial timbers of India.  Gov.  of India Central Publ. Br., Calcutta.

 

From: Chudnoff, Martin. 1984. Tropical Timbers of the World. USDA Forest Service. Ag. Handbook No. 607.