Description from Flora of China
Alstonia glaucescens (Wallich ex G. Don) Monachino; Alstonia pachycarpa Merrill & Chun; Alyxia glaucescens Wallich ex G. Don, not Wallich; Winchia calophylla A. de Candolle, not Alstonia calophylla Miquel; W. glaucescens (Wallich ex G. Don) K. Schumann.
Trees evergreen, glabrous, to 30 m tall. Branches greenish, angled when young. Leaves in whorls of 3 or 4, rarely opposite; petiole 1-2 cm; leaf blade narrowly elliptic, 7-20 X 2.5-4.5 cm, thick papery, lustrous adaxially, paler abaxially, apex caudate or acuminate; lateral veins 20-50 pairs, at 80-90° to midvein. Cymes glabrous, ca. 4 cm; peduncle 1.5-3 cm. Pedicel to 3 mm. Corolla white, pubescent, tube 5-6 mm; lobes broadly ovate, 3-4 mm, overlapping to left. Disc absent. Ovaries connate. Follicles connate, 18-35 X 1-1.2 cm. Seeds narrowly elliptic; cilia brown-yellow, to 2 cm. Fl. Apr-Jul, fr. Aug-Dec.
The wood is used for making furniture and stationery, and the leaves and bark are used to treat acute bronchitis.
Monsoon or montane rain forests; 300-1100 m. Hainan, S Yunnan [India, Indonesia, Malaysia, Myanmar, Thailand]