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The hairpin banksia (''Banksia spinulosa'') is a species of woody shrub, of the genus ''Banksia'' in the Proteaceae family, native to eastern Australia. Widely distributed, it is found as an understorey plant in open dry forest or heathland from Victoria to northern Queensland, generally on sandstone though sometimes also clay soils. It generally grows as a small shrub to in height, though can be a straggly tree to . It has long narrow leaves with inflorescences which can vary considerably in coloration; while the spikes are gold or less commonly yellowish, the emergent styles may be a wide range of colours – from black, purple, red, orange or yellow. ''Banksia spinulosa'' was named by James Edward Smith in England in 1793, after being collected by John White, most likely in 1792. He gave it the common name prickly-leaved banksia, though this has fallen out of use. With four currently recognised varieties, the species has had a complicated taxonomic history, with two varieties initially described as separate species in the early 19th century. A fourth, from the New England region, has only recently been described. However, there has been disagreement whether one, var. ''cunninghamii'', is distinct enough to once again have specific status. The pre-eminent authority on ''Banksia'', Alex George, concedes there is still more work to be done on the ''Banksia spinulosa'' complex. The hairpin banksia is pollinated by and provides food for a wide array of vertebrate and invertebrate animals in the autumn and winter months. Its floral display and fine foliage have made it a popular garden plant with many horticultural selections available. With the recent trend towards smaller gardens, compact dwarf forms of ''Banksia spinulosa'' have become popular; the first available, ''Banksia'' 'Birthday Candles', has achieved a great deal of commercial success and wide recognition, and has been followed by several others. ==Description== The hairpin banksia usually occurs as a multi-stemmed lignotuberous shrub tall and across. Alternatively, it may be single-stemmed and lacking a lignotuber, in which case it is often taller, up to high. It has grey or grey-brown smooth bark with lenticels. The long, narrow leaves are in length, 1–8 mm wide and more or less linear in shape. Leaf edges are either serrate for the entire leaf length (''collina'') or toward the apex only (''spinulosa''),〔 though the margins may be recurved and hence serrations not evident as in those from the Carnarvon Gorge. Immature leaves, which may also be seen after bushfire, are broader and serrated. Leaf undersides have fine white hairs in the case of the varieties ''spinulosa'' and ''collina'' and pale brown in ''cunninghamii'' and ''neoanglica''.〔 The distinctive inflorescences or flower spikes occur over a short period through autumn and early winter. A spike may contain hundreds or thousands of individual flowers, each of which consists of a tubular perianth made up of four united tepals, and one long wiry style. Characteristic of the taxonomic section in which it is placed, the styles are hooked rather than straight. The style ends are initially trapped inside the upper perianth parts, but break free at anthesis. In ''Banksia spinulosa'' the spikes are cylindrical, about wide and tall, yellow to golden orange in colour, with styles varying from yellow to pink, maroon, or black.〔 Styles of various colours may be found within metres of each other in some areas such as in the Georges River National Park, and Catherine Hill Bay, while other populations may have uniformly black, red or gold styles. Though not terminal, the flower spikes are fairly prominently displayed. Partly emerging from the foliage, they arise from two- to three-year-old stem nodes. The hairpin banksia's infructescence is a typical ''Banksia'' cone-like structure, with up to 100 crowded embedded follicles which are 1–2.4 centimetres (⅓–1 in) in diameter; these generally remain closed until burnt by bushfire. The nonlignotuberous subspecies ''cunninghamii'' is killed by fire and regenerates from seed, while the others regenerate from buds around the base of the lignotuber.〔 Old flower spikes fade to brown, then grey with age. Old flower parts usually persist for a long time, giving the infructescence a hairy appearance.〔 In Central and North Queensland, old cones of both var. ''spinulosa'' and var. ''collina'' are generally bare.〔 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 spinulosa」の詳細全文を読む スポンサード リンク
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