Durio graveolens Becc.

A large tree up to 50 m tall, with straight, cylindrical bole branchless for up to 25 m and up to 100 cm in diameter having steep buttresses up to 3 m high, bark surface smooth, finely cracked or flaky, reddish-brown or greyish-mauve. Leaves elliptical to oblong, 10-26 cm x 4-10 cm, densely copper-brown scaly below. Flowers in short cymes on branches, petals 25-35 mm long, white, stamens in 5 bundles, opening by a slit. Fruit a globose to ellipsoid capsule, about 10-15 cm in diameter, outside orange-yellow, with sharp pyramidal 1 cm long spines, dehiscent into 5 valves while still attached to the branch. Seeds ellipsoid, 4 cm x 2 cm, glossy brown, completely enclosed by a fleshy dark red aril D. graveolens closely resembles D. dulcis but differs in the colour of the fruit. Moreover, the fruit opens while still on the tree showing the dark red arils, whereas the fruit of D. dulcis drops unopened and has dark yellow arils.

Flowering within 6 years after sowing. Pollen of D. graveolens has been found in guano samples from Eonycteris spelaea, a nectarivorous bat, thus indicating that flowers of these species are pollinated by bats.

D. graveolens occurs in lowland forest, in Sarawak on clay-rich soils in mixed dipterocarp forest and on shale ridges.

Peninsular Thailand, Peninsular Malaysia, Sumatra and Borneo (Sabah, Sarawak, Kalimantan); also cultivated in Sabah and Brunei.

The germination rates for fresh seed of D. graveolens is 95% in 5-19 days.

Food: The aril around the seed is edible but not very juice, hardly fragrant and not very tasty. Timber: The wood is used as durian. D. graveolens is one of the important sources of durian timber in Sarawak.