Palmae is a plant group with unique landscaping function ("palm landscape"), and is also one of the three most important economic plant groups in the world, including coconut, which is known as one of the ten most important trees in the world, jujube, which is known as the tree of life, and oil coconut, which ranks first in the world edible oil trade. [2] In addition, the stems of Arenca catechu and some species are rich in starch, which can be extracted for food; Sugar coconut and inflorescence of some fishtail anemones can shed a lot of juice after being cut, which can be evaporated into sugar or fermented into soju; Some kinds of wood are hard and can be used as building materials; Leaves can be roof coverings or woven hats or baskets; The leaves of the anemone can be fans; The fiber of the leaf sheath (i.e. brown coat) and the fiber of the coconut shell can be woven into ropes, woven into clothes or used as brooms; Areca nut is used as medicine or dye. Palmae is divided into 5 subfamilies: 1. Calamoideae There are 21 genera of woody vines, arbors or shrubs, mainly in tropical Asia. This subfamily produces a variety of important economic products. For example, the provincial rattan is an important rattan resource in Southeast Asia, which is used to weave various exquisite furniture and utensils. Its stem is more than 200 meters long, and it is also produced in southern China. Dragon's Blood is a famous original plant of Dragon's Blood. Its fruit can be used to extract red resin for Chinese medicine Dragon's Blood or dyeing pigment. Sago coconut is produced in Southeast Asia, Papua New Guinea and other places. The pith of the trunk can be made into sago rice (sago) as the main food. 2. Nypoiseae One genus and one species, namely water coconut, are distributed in tropical Asia and Oceania, extending north to Hainan Island and Taiwan, China, and often grow in the bay mud bogs or mixed in mangroves; It often has the habit of viviparity; The pulp can be eaten or eaten after being salted; The juice from the inflorescence axis can be used to make drinks; Leaves for weaving, building, etc. Stolon, tufted. Leaves pinnate, lobes outward folded. The flowers are unisexual, monoecious, but the female and male inflorescences are heteromorphic. The female flowers gather at the top of the stem to form a spherical cyme, and the male flowers are on the short lateral spikes; 6 perianth segments, linear, 3 stamens, filaments united into columnar; 3 carpels, free. The fruit is spherical, composed of flattened and angular carpels, with or without seeds. The semi mangrove and mangrove constructive species growing in tropical coastal marsh soil are also relict plants, which are valuable for studying the phylogeny and origin of palmae, tropical flora, paleontology, paleogeography, etc. The juice on the inflorescence of flame contains about 15% sucrose; Edible kernel; Its leaf can be used to build houses and woven mat baskets and other handicrafts; It also has the functions of preventing wind and waves, strengthening sea walls, greening the coast and purifying the air. three