Sibakong is a shrub or small tree with milky juice which reaches a height of about 15 meters but usually smaller. Leaves are ornamental, occurring in whorls, lanceolate, 6 to 12 cm in length, 1.5 to 3 cm in width, rather narrow and sharply pointed at both ends. Flowers are small, white, fragrant and borne on compound inflorescences. Fruit is somewhat rounded, about 8 mm in diameter, and obscurely two-lobed.
In thickets and secondary forests at low and medium altitudes in Cagayan, Ilocos Norte, Isabela, Pangasinan, Nueva Ecija, Batangas, Camarines Provinces in Luzon; also in Mindoro, Lubang, Masbate, and Mindanao.
New buds used for stomach disorders of young babies.
• Isolation of reserpine and rescinnamine from Rauwolfia amsoniaefolia A. DC.