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The wood anatomy and chemistry of a relatively lesser used wood species, known in Mozambique as nsangala (Millettia mossambicensis J.B. Gillett) was compared to overexploited species jambire (Millettia stuhlmannii Taub) to provide diagnostic features for safe discrimination. The anatomical results showed that both species shared several similarities such as intervessel pitting size range (8 micrometres to 11 micrometres), rays composed of only procumbent cells, fiber dimensions (average length up to 1359 micrometres and wall thickness up to 10 micrometres) and banded axial parenchyma. The extractives and lignin content were higher in jambire, while the carbohydrates and acetyl contents were higher in nsangala. The main anatomical feature separating the two species was the porosity pattern with semi-ring porous wood of nsangala compared to the diffuse-porous structure of jambire. Jambire had wider vessel lumina (200 micrometres) and up to 3 vessels/mm2 compared to nsangala vessel lumina of 86 micrometres and a frequency of 37 vessels/mm2.

Scots pine and Norway spruce, the most used commercial wood species in Europe, were thermally treated under industrial conditions by steam (Thermowood®) and vacuum (Termovuoto). Matched boards were treated, and the alterations in chemistry, color, mass loss, mechanical properties, and durability were compared. In treatments at identical temperature and duration, Thermowood® and the thermo-vacuum process caused similar mass loss in both wood species. The thermal treatments showed minor effects on the released acetic acid during the thermal degradation of polysaccharides. The equilibrium moisture content correlated well with the mass loss and confirmed indirectly the similarity of the two processes. The chemical composition and durability of the two groups of treated wood were similar. In conclusion, Thermowood® and thermo-vacuum treatments according to Termovuoto technology both produce similar final products with regard to chemical composition, physical-mechanical properties, and durability, with some differences in the appearance.