2. Pandanus Parkinson, J. Voy. South Seas. 46. 1773.
露兜树属 lu dou shu shu
Trees, shrubs, or herbs, evergreen, dioecious. Stems simple or branched, erect or prostrate, often with stiltlike, verrucose prop roots and aerial roots, sometimes virtually absent, often suckering. Leaves simple, terminal, sessile, densely arranged in corkscrew spirals, 3- or 4-seriate, linear, often spinose-serrate on margin and on keeled midvein abaxially. Inflorescence of large, bracteate heads or spadices; perianth absent. Male inflorescence paniculate with spiciform branches subtended by secondary, usually colored, spathes, branches covered with numerous stamens; flowers not individually distinguishable. Female inflorescence of globose to cylindric clusters or several-carpelled aggregates; flowers not individually distinguishable; carpels 1-ovuled; staminodes absent in female flower; placentation subbasal. Fruit a hard drupe, syncarpous, comprising an aggregation of individual connate, angled, fibrous phalanges; mesocarp sometimes hollow; exocarp fleshy; endocarp woody or bonelike; locules 1 or more; phalanges separating at maturity; stigma persistent, capitate. Seed solitary.
About 600 species: Old World tropics; six species (one endemic, one introduced) in China.
Pandanus utilis Bory, native to Madagascar and cultivated in China, unlike most other species, is both non-suckering and has reddish purple marginal spines (see FRPS 8: 23. 1992; Check List Hong Kong Pl. 297. 2002). Pandanus boninensis Warburg, native to Japan, is also cultivated in China (see FRPS 8: 23. 1992). Pandanus utilis and P. boninensis are cultivated at the Taiwan Forestry Research Institute, as is P. pygmaeus Thouars of the Mascarenes (pygmy plant ca. 40 cm).