Polyalthia suberosa (Roxburgh) Thwaites, Enum. Pl. Zeyl. 398 (1864)

Species name meaning 'corky', referring to the stem and twigs.

Guatteria suberosa (Roxb.) Dunal
Phaeanthus cumingii Vidal
Phaeanthus malabaricus Naves
Uvaria suberosa Roxb.

Small shruby tree, with very characteristic thickly ridged corky bark, but young twigs nicely red-brown with white dots (lenticels). From a distance the leaves look alternate spirally arranged although on closer inspection they are alternate in two rows. Flowers solitary (sometimes two) either leaf opposed or slightly below the leaf, whitish-green. Fruits apocarpous, with up to 18 stalked carpels which turn red when ripe, each with 1-2 seeds.

Shrubs or small trees, to 5 m tall. Bark corky, ridged. Branchlets dark red, rust-colored pubescent when young, glabrescent, with pink lenticels and corky ridges when older. Petiole 2-4 mm, puberulent; leaf blade oblong, elliptic-oblong, or narrowly obovate-oblong, 5-11 x 2-4 cm, membranous to papery, abaxially pale brown when dry and glabrescent, adaxially gray and glabrous except for sparse pubescence along midvein, secondary veins 8-10 on each side of midvein, spreading, and inconspicuous on both surfaces, reticulate veins lax and inconspicuous, base narrowed and slightly oblique, apex subobtuse to rounded and sometimes abruptly shortly acuminate. Inflorescences extra-axillary, leaf-opposed, or slightly below leaf, 1(or 2)-flowered. Pedicel 0.7-2.5 cm, puberulent; bracteole near base of pedicel, minute, apex acute. Sepals ovate-triangular, 2-2.5 mm, outside pubescent, inside glabrous. Petals yellowish green; outer petals oblong-lanceolate, shorter than inner petals, leathery, flat and spreading, outside slightly pubescent, inside glabrous, apex acute; inner petals oblong, erect and curved, ca. 10 mm, apex obtuse. Stamens many, ca. 1 mm; connectives apically convex. Carpels many, ca. 2 mm, pubescent; ovules 1 or 2 per carpel; styles widening into a thickly triangular bladelike glabrous stigma. Monocarp stipes 8-10 mm, slender; monocarps to 18, red, almost spherical, ca. 5 mm in diam., sparsely appressed pubescent or glabrescent. Seeds 1 or 2 per monocarp, with a longitudinal circumferential band. [from Flora of China]

Open forests at lower elevations. The thick, corky bark, is probably an adaptation to fire.

Ripe fruits are edible. Decoction of fresh roots used as abortifacient, relieves abdominal pain caused by muscular cramps; increases milk secretion. In Bangladesh, the bark is used as febrifuge analgesic, and laxative. In the tropics, latex is used as crude filling for tooth cavities.

Sri Lanka and India into southern China and Hainan and Southeast Asian mainland (Indochina), Peninsular Malaysia and the Philippines.

Local names
Bangladesh: Jam debharu, Ham jam.
China: An luo, Ji zhao shu, Lao ren pi, Mei wei mu, Shin guan yin.
English: Corky debbar tree.
India: Gua koli.
Philippines: Baling-manok (Tag.), Duhat-duhatan (Tag.), Duhat-matsing (Tag.), Duyat-nasi (Pamp.), Lanutan (Tag.), Tagputagpuan (Tag.), Munat (Iik.).
Thailand: Klueng klom.