Sugar gum tree (scientific name: Alstonia scholaris), also known as elephant skin tree, lampstand tree, blackboard tree, milk tree, devil tree, etc. , belonging to the genus lampstand of Apocynaceae. Originated in South Asia with high temperature and humidity, the wood is soft and delicate, and the whole plant is rich in milk, from which chewing gum raw materials can be extracted, hence the name "Sugar Gum Tree". Wood can be used as blackboard material, so it is called blackboard tree.
Trees, 20 meters high and about 60 centimeters in diameter (40 meters high and 1.25 meters in diameter recorded abroad); Branches are whorled, milky white, glabrous. 3-8 impellers, obovate oblong, oblanceolate or spoon-shaped, ovophobic or oblong, 7-28 cm long and 2- 1 1 cm wide, hairless, round at the top, dull or slightly concave, sparse and sharp or gradually sharp, and wedge-shaped at the base; There are 25-50 lateral veins on each side, which are close and parallel, almost horizontally transverse to the leaf margin; Petiole length 1.0-2.5 cm. Flowers are white, many flowers form dense cymes, terminal and pilose; The total pedicel is 4-7 cm long; Pedicel is about 65438 0 mm long; Corolla saucer-shaped, corolla tube 6- 10 mm long, swollen above the middle, with pilose inner surface, lobes covering to the left at bud or lobe base, oblong or ovoid, 2-4 mm long and 2-3 mm wide; Stamens oblong, about 65438 0 mm long, inserted in the expanded corolla tube; Ovary is composed of two free carpels, densely pilose, filiform, 4.5 mm long, with rod-shaped stigma and two separate tips; The disc is annular. Slender, linear, 20-57 cm long, epicarp nearly leathery, grayish white, 2-5 mm in diameter; The seeds are oblong and reddish-brown, with reddish-brown cilia at both ends, and the cilia are 1.5-2 cm long. The flowering period is June-165438+10, and the fruiting period is June-June-April of the following year.