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''Juniperus bermudiana'' is a species of juniper endemic to Bermuda. This species is most commonly known as Bermuda cedar, but is also referred to as Bermuda juniper. It is an evergreen tree growing up to 15 m tall with a trunk up to 60 cm thick (larger specimens existed in the past) and thin bark that exfoliates in strips. The foliage is produced in blue-green sprays, with the individual shoots 1.3–1.6 mm wide, four-sided (quadriform) in section. The leaves are scale-like 1.5–2.5 mm long (up to 4 mm long on strong-growing shoots) and 1-1.5 mm broad, with an inconspicuous gland; they are arranged in opposite decussate pairs, occasionally decussate whorls of three. Juvenile plants bear needle-like leaves 4–8 mm long. The seed cones are irregularly globose to broad pyriform, 4–6 mm long and 5–8 mm broad, soft and berry-like, green at first, maturing bluish-purple about 8 months after pollination; they contain one or two (rarely three) seeds. The male cones are 4–6 mm long, yellow, turning brown after pollen release in early spring. == Ecology == A threat to the continued existence of Bermuda's junipers arose in the mid-1940s when the species was attacked by two species of scale insects, ''Lepidosaphes newsteadi'' and ''Carulaspis minima'', which were unintentionally introduced from the United States' mainland during the wartime construction of US airbases in Bermuda. By 1978, these parasites had killed 99% of Bermuda's junipers, some 8 million trees. However, the remaining 1% of the trees proved somewhat resistant to the scale insects, and efforts by Bermuda's Department of Agriculture, Fisheries and Parks to plant young junipers from this resistant strain throughout Bermuda have saved the trees from extinction. In the 1950s and 1960s, the casuarina (''Casuarina equisetifolia'', also known as horsetail tree and Australian pine), native to Australia, was introduced into Bermuda to replace the Bermuda cedar's windbreak functions. However in Bermuda, casuarinas have proved to be highly aggressive, and no other plants are able to survive beneath them. Still, like the Bermuda cedar, the casuarina's foliage is resistant to wind and salt, and these features have made casuarinas popular with gardeners in Bermuda. Other species introduced in an attempt to replace the juniper forest included the bay grape (''Coccoloba uvifera''). Along with the casuarina, the juniper's main introduced competitor for space is the Brazilian pepper (''Schinus terebinthifolius''). The species is occasionally grown as an ornamental tree outside of Bermuda, and may have become naturalised on Hawaii and Saint Helena. It is reported that more than 6,500 of them were planted in Hawaii between 1921 and 1953, and that it has established wild populations there.〔 〕 The Bermuda cedar forests that covered Bermuda fed and housed many species of bird that had evolved and adapted to live amongst them, and thus became endemic to Bermuda. With the loss of so many trees the populations of such species have plummeted to near extinction. These birds include the Bermuda white-eyed vireo, and a possible subspecies of eastern bluebird. Efforts by the public and the government have been made to boost their populations along with the populations of the Bermuda cedar. However the Bermuda cedar may take 200 years to reach full maturity, and the birds may not survive this long. With recent sea level rises, some low-lying old-growth cedars are being infiltrated with seawater and are beginning to die off. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Juniperus bermudiana」の詳細全文を読む スポンサード リンク
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