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''Banksia menziesii'', commonly known as firewood banksia, is a species of flowering plant in the genus ''Banksia''. It is a gnarled tree up to tall, or a lower spreading shrub in the more northern parts of its range. The serrated leaves are dull green with new growth a paler grey green. The prominent autumn and winter inflorescences are often two-coloured red or pink and yellow, and their colour has given rise to more unusual common names such as port wine banksia and strawberry banksia. Yellow blooms are rarely seen. First described by the botanist Robert Brown in the early 19th century, no separate varieties of ''Banksia menziesii'' are recognised. It is found in Western Australia, from the Perth (32° S) region north to the Murchison River (27° S), and generally grows on sandy soils, in scrubland or low woodland. ''Banksia menziesii'' provides food for a wide array of invertebrate and vertebrate animals; birds and in particular honeyeaters are prominent visitors. A relatively hardy plant, ''Banksia menziesii'' is commonly seen in gardens, nature strips and parks in Australian urban areas with Mediterranean climates, but its sensitivity to dieback from the soil-borne water mould ''Phytophthora cinnamomi'' makes it short-lived in places with humid summers, such as Sydney. ''Banksia menziesii'' is widely used in the cut flower industry both in Australia and overseas. == Description == ''Banksia menziesii'' grows either as a gnarled tree to , or a lower spreading shrub, generally encountered at its northern limits in the vicinity of Eneabba-Mount Adams; thus, it declines steadily in size as the climate becomes warmer and dryer further north. In the shrub form, several stems arise from the woody base known as the lignotuber. The trunk is greyish, sometimes with shades of brown or pink, and the thick rough bark breaks away easily. The new growth is covered in fine brownish hair, which wears away after two or three years, leaving smooth stems and leaves.〔 Stems that will bear flower spikes the following year are generally thicker and longer. Oblong in shape and somewhat truncate at the tips, the leaves are grey-green in colour, long and up to wide. The new leaves are paler and finely downy. The leaf margins are serrated with many small 1–2 mm long triangular teeth. The lower surface of the leaf has a midrib covered in fine pale brown hair.〔 Flowering occurs in autumn and winter, peaking from May to July. Overall the inflorescences, or flower spikes, take around eight months to development from the first microscopic changes in late spring. Ovoid to cylindrical in shape, the flower spikes can be up to wide and high. They are composed of numerous individual flowers; one field study south of Perth recorded an average of 1043 per flower spike, while another on plants in cultivation in South Australia recorded an average of 720. ''B. menziesii'' has more flower colour variants than any other ''Banksia'' species, with flower spikes occurring in a wide range of pinks, as well as chocolate, bronze, yellow and white, and greenish variants. They are particularly striking closeup but can look indistinct from a distance. They are most attractive in late bud, the styles contrasting well to the body of the inflorescence, the whole looking like a red- or pink-and white vertical candy striped bloom. The inflorescences are generally a deeper red after colder weather and further into the winter.〔Collins, ''et al''. pp. 266–67.〕 Anthocyanin pigments are responsible for the red and pink shades in the flowers. Old flowers usually fall off the spikes quickly, with up to 25 large beaked follicles developing. A mottled dark brown and grey in colour, these can be prominent and quite attractively patterned when newly developed. Oval shaped, they are long by high and wide.〔 Overall, only a small fraction of flowers develop into follicles; the proportion is as low as one in a thousand. The plant is dependent on fire to reproduce as the follicles only open after being burnt, each one producing one or two viable wedge-shaped (cuneate) seeds, on either side of a woody separator.〔 The colour and level of pigmentation in the seeds foreshadows the eventual colour of the inflorescences. Kevin Collins of the Banksia Farm recalled that for many years pale seeds were discarded by seed collectors who thought they were infertile. Later, he learnt that pale seeds yielded yellow-coloured blooms, dark grey the usual red-coloured, and black a distinctive bronze-coloured bloom. Seedlings have obovate cotyledons long by wide, and the leaves that develop immediately afterward are crowded and very hairy. They have serrate margins.〔 Evidence of thickening to form a future lignotuber, as well as minute buds, has been detected from the bases of seedlings at five months of age. 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「Banksia menziesii」の詳細全文を読む スポンサード リンク
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