1, Luan tree, alias: Mu Luan, Luan Hua, etc. It is a plant of Luanshu in Sapindaceae. Deciduous trees or shrubs; Thick bark, light gray brown to light gray black, longitudinally cracked when old; Small lenticels, gray to dark brown; Branchlets with verrucous spots, and leaf rachis and petiole are wrinkled pubescent or glabrous.

2. Koelreuteria paniculata grows in calcium-based soil produced by limestone weathering and is cold-resistant. In China, it is only distributed in the lower reaches of the Yellow River basin and the Yangtze River basin, and it is rare in the north of the Haihe River basin, so it can't grow in silicon-based acidic red soil areas. Luan tree germinates late in spring and leaves early in autumn, so the annual growth period is short and slow. Wood can only be used to make small household appliances, and seeds can be squeezed into industrial oil.