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(Sciadopitys verticillata), coniferous evergreen tree native to Japan, the only member of the umbrella pine family (Sciadopityaceae). Historically, this genus was classified variously in Cupressaceae or Taxodiaceae, but subsequent studies confirmed its structural uniqueness. Although slow growing, it may reach a height of 36 metres (116 feet), with a trunk diameter of 1.2 metres (4 feet). The short branches are arranged in circles about the trunk. The small, scalelike leaves are less than 6 mm (0.2 inch) long and adhere closely to the bark. Modified shoots assuming the form and function of leaves occur in umbrella-like whorls of 15 to 35 at the tips of the twigs. Several varieties of the umbrella pine are cultivated as ornamentals. Its wood is used in making boats; its bark, in the form of oakum, is used for caulking.