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''Banksia brownii'', commonly known as feather-leaved banksia or Brown's banksia, is a species of shrub that grows in southwest Western Australia. An attractive plant with fine feathery leaves and large red-brown flower spikes, it usually grows as an upright bush around two metres (7 ft) high, but can also occur as a small tree or a low spreading shrub. First collected in 1829 and published the following year, it is placed in ''Banksia'' subgenus ''Banksia'', section ''Oncostylis'', series ''Spicigerae''. There are two genetically distinct forms. ''B. brownii'' occurs naturally only in two population clusters between Albany and the Stirling Range in southwest Western Australia. In the Stirling Range it occurs among heath on rocky mountain slopes; further south it occurs among jarrah woodland in shallow nutrient-poor sand. It is rare and endangered in its natural habitat, with all major populations currently threatened by ''Phytophthora cinnamomi'' dieback, a disease to which the species is highly susceptible. Other threats include loss of habitat, commercial exploitation and changes to the fire regime. Highly valued by Australia's horticultural and cut flower industries, ''B. brownii'' is widely cultivated in areas not exposed to dieback. It prefers a sheltered position in soil with good drainage, and must be provided with some moisture over summer. == Description == ''B. brownii'' usually grows as an upright bush between one and three metres (3–10 ft) high, but it can also grow as an openly branched small tree to six metres (20 ft) in sheltered gullies, or as a low, spreading shrub in exposed locations such as the peaks of the Stirling Range. The bark is a grey-brown colour, smooth and thin, with lenticels. The leaves are long and thin, from three to ten centimetres (1–5 in) long, and five to ten millimetres (– in) wide. Dark green and hairless above but with a hairy white underside, they are easily recognised by their feather-like appearance, caused by the fact that they are finely divided almost back to the midrib, into as many as 70 thin tapered lobes. Flowers occur in typical ''Banksia'' "flower spikes", inflorescences made up of hundreds of pairs of flowers densely packed in a spiral around a woody axis. ''B. brownii'' Flower spikes are held erect and are typically terminal on a branch; often other branchlets grow up and around a spike from below. The fruiting structure is a stout woody "cone", around five centimetres (2 inches) in diameter, with a hairy appearance caused by the persistence of old withered flower parts. A "cone" may be embedded with up to 60 follicles,〔 although usually there are very few or even none at all. Unusually for ''Banksia'', each follicle contains just one seed. This is shiny black, oval in shape, about 20 millimetres (¾ in) long, with a brown papery wing.〔〔 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 brownii」の詳細全文を読む スポンサード リンク
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