Color/Appearance: Heartwood is light to golden brown, not clearly demarcated from the sapwood. Intermittent latex canals are sometimes present and appear as slits in the wood. The wood can also be susceptible to fungal staining if not dried properly. Grain/Texture: Grain is usually straight or slightly interlocked. With a fine to medium texture and low natural luster. Rot Resistance: Rated as perishable; poor insect resistance. Workability: Easy to work with both hand and machine tools. Poor bending properties. Turns, glues, and finishes well. Odor: Can have a strong unpleasant odor when green, diminishing somewhat in dry wood. Allergies/Toxicity: Although there have been no reports of health reactions with Siam balsa, other closely related species in the Alstonia genushave been reported to cause skin irritation—possibly in conjunction with the latex canals found in the trunk. See the articles Wood Allergies and Toxicityand Wood Dust Safetyfor more information. Pricing/Availability: Most pulai that’s used commercially is harvested from South and Southeast Asia. The lighter root wood is sometimes recovered as driftwood and used domestically on a limited basis. Prices are low within its natural range. Sustainability: This wood species is not listed in the CITES Appendices, and is reported by the IUCN as being a species of least concern. Common Uses: Utility wood, plywood, carvings, crates, and boxes. The lighter root wood is used as a substitute for cork, as well as rafts and pith helmets. Comments: The regular trunk wood of Alstonia spatulata is very closely related to Indian pulai (Alstonia scholaris)and is also sold under the trade name pulai (or alternatively, as hard milkwood—so named for the milk-like latex that is exuded from the tree). However, the root wood of the tree bears extremely soft and lightweight wood that’s been compared to styrofoam. The root wood is so soft that it is still scientifically unexplainedas to how such material could bear up an entire tree. One hypothesis is that the trees are simply not very strong, and easily storm damaged, which may help explain the predominance of large chunks of the buoyant trunk recovered as driftwood in the Central Pacific. Despite its common name, Siam balsa is not closely related to true balsa (Ochroma pyramidale). |