Dalbergia Congestiflora Standl.: Wood Structure And Physico-Chemical Properties Compared With Other Central American Species Of Dalbergia

Wood structure and selected physico-chemical properties of a rare Mexican species, tentatively identified as Dalbergia congestiflora, are described and compared with other Central American species of Dalbergia. On account of their distinct wood structure, four species groups can be distinguished: 1) D. granadillo, D. hypoleuca, D. lineata and D. retusa ('cocobolo') are characterised by mainly apotracheal diffuse-inaggregates parenchyma, large and few vessels, high density (0.89-1.35 g/cm3), identical heartwood colour, and chemical composition of extractives (D. granadillo, D. retusa); 2) D. tucuruensis (including D. cubitquitzensis) and D. palo-escrito are identical in all aspects but distinct from the coco bolo group on account of differences in parenchyma distribution, heartwood colour and extractives composition (D. tucuruensis), and the consistently lower density (~0.80 g/cm3); 3) D. congestiflora and D. funera (= D. calderonii) differ markedly in heartwood colour and somewhat in heartwood extractives composition but share a high density and similar wood structural pattern characterised primarily by relatively small and frequent vessels, banded parenchyma and the presence of prismatic crystals in ray cells; 4) D. stevensonii is very similar in wood structure to D. tucuruensis but has a much higher density and different heartwood extractives composition. These results indicate that the combination of wood structure and chemistry of heartwood extractives may be successfully employed for intrageneric classification of Dalbergia.