Meliaceae is an economically important family of tropical and subtropical trees and shrubs. It includes some of the most highly prized timber-trees in the world. The commercial mahoganies from Swietenia and Khaya are prime examples. Other members include the ‘Neem Tree’ (Azadirachta indica) which is an important source of pharmaceuticals and cosmetic products. Several popular fruit trees in Peninsular Malaysia such as ‘Langsat’ (Lansium domesticum) and ‘Sentol’ (Sandoricum koetjape) are also members to this family.
Dysoxylum Blume is one of the genera in Meliaceae. This genus comprises about 80 species occurring in India and Sri Lanka to Myanmar, Indo-China, southern China, Thailand and throughout the Malesian region, east towards the Pacific islands and south towards Australia and New Zealand. Seventeen species are found in Peninsular Malaysia. The preferred uses of the timber of Dysoxylum species in Peninsular Malaysia include flooring, furniture, wall panelling, solid door construction, veneer and plywood.
Dysoxylum cauliflorum was first described in 1875 by Hiern in the “Flora of British India” based on a collection from Malacca by Maingay. The species name derived from the Latin words ‘caulis’ means stem and ‘flos’ means flower that refer to the position of the flowers on the stem. Compared with the other two Dysoxylum species in Peninsular Malaysia that also have spirally arranged leaves and terminal leaflet (Dysoxylum arborescens and D. densiflorum), the cauliflorous inflorescence is the distinctive character that differentiates this species. It is a common tree from Southeast Asia and west Malesia, eastwards to Borneo and Palawan where it occurs in rain forest up to 1500 m altitude. It is common throughout Peninsular Malaysia. The vernacular names of this plant in Peninsular Malaysia are ‘dedali’, ‘langga ayer’ and ‘pokok parong’.
Dysoxylum cauliflorum is characterized as a medium-sized tree up to 30 m tall and 50 cm diameter. The grey bark is smooth, lenticellate and bosses of defunct inflorescences to mottled brown with rectangular flakes. The fawn inner bark has sour smell. The leaves are imparipinnate and consist of 5 to 6 pairs of leaflet. The petioles are swollen at the base. The leaflets are oblong-elliptic, the base is cuneate or rounded very unequally, the apex is acuminate, sparsely pubescent to densely rusty tomentose particularly on abaxial surface of veins and adaxial surface of the midrib. The secondary veins are 8 to 13 pairs while the tertiary veins are reticulate. The inflorescences are in spikes, situated on persistent woody tubercles on bole almost from ground level or along the branches (rarely in axils of the old leaves). The pedicels are pubescent. The flowers are intensely fragrant of almonds and musk. The calyx are cupular with 3 or 4 irregular, shallow teeth, pubescent. The petals are 3 to 4, linear-oblong, acute, glabrous, white to pinkish or creamish. The fruits are solitary or in cluster, ovoid, sometimes 3–4-angled or weakly winged, blunt, glabrous, ripening rose-red, splitting into four valves with each valve bright orange within. The pericarps are with milky latex. The seeds are 1 to 4, born on white placenta and with the aril covering half of the testa.