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''Melaleuca'' is a genus of nearly 300 species of plants in the myrtle family, Myrtaceae, commonly known as paperbarks, honey-myrtles or tea-trees (although the last name is also applied to species of ''Leptospermum''). They range in size from small shrubs which rarely grow to more than high, to trees up to . Their flowers generally occur in groups, forming a “head” or “spike” resembling a brush used for cleaning bottles, containing up to 80 individual flowers. They are superficially like ''Banksia'' species, which also have their flowers in a spike, but the structure of individual flowers in the two genera are very different. Second only to members of the family Proteaceae, melaleucas are important food sources for nectarivorous insects, birds, and mammals. Many are popular garden plants, either for their attractive flowers or as dense screens and a few have economic value for producing fencing and oils such as “tea tree” oil. Most melaleucas are endemic to Australia, with a few also occurring in Malesia. Seven are endemic New Caledonia, and one is found only on the (Australian) Lord Howe Island. Melaleucas are found in a wide variety of habitats. Many are adapted for life in swamps and boggy places, while others thrive in the poorest of sandy soils or on the edge of saltpans. Some have a wide distribution and are common, whilst others are rare and endangered. Land clearing, exotic myrtle rust, and especially draining and clearing of swamps threaten many species. ==Description== Melaleucas range in size from small shrubs such as ''Melaleuca aspalathoides'' and ''Melaleuca concinna'' which rarely grow to more than high, to trees like ''Melaleuca cajuputi'' and ''Melaleuca quinquenervia'', which can reach . (One specimen of ''M. cajuputi'' reached .) Many, like ''Melaleuca linariifolia'', are known as paperbarks and have bark that can be peeled in thin sheets, whilst about 20% of the genus, including ''Melaleuca bracteata'', have hard, rough bark and another 20% have fibrous bark. Every species in the genus is an evergreen and the leaves vary in size from minute and scale-like (''Melaleuca micromera'') to long (''Melaleuca leucadendra''). Most have distinct oil glands dotted in the leaves, making the leaves aromatic, especially when crushed. Melaleuca flowers are usually arranged in spikes or heads. Within the head or spike, the flowers are often in groups of two or three, each flower or group having a papery bract at its base. Five sepals occur, although these are sometimes fused into a ring of tissue and five petals which are usually small, not showy and fall off as the flower opens or soon after. The stamens vary greatly in colour, from white to cream or yellow, red, or mauve with their yellow tips (the anthers) contasting with their "stalks" (filaments).〔 The fruits are woody, cup-shaped, barrel-shaped, or almost spherical capsules, often arranged in clusters along the stems. The seeds are sometimes retained in the fruits for many years, only opening when the plant, or part of it, dies or is heated in a bushfire. In tropical areas, seeds are released annually in the wet season.〔 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「Melaleuca」の詳細全文を読む スポンサード リンク
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