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''Banksia coccinea'', commonly known as the scarlet banksia, waratah banksia or Albany banksia, is an erect shrub or small tree in the family Proteaceae. Endemic to south west Western Australia, it occurs from Denmark to the Stokes National Park, and north to the Stirling Range, growing on white or grey sand in shrubland, heath or open woodland. Reaching up to in height, it is a single-stemmed plant that has oblong leaves, which are long and wide. The prominent red and white flower spikes appear mainly in the spring. As they age they develop small follicles that store seeds until opened by fire. Though widely occurring, it is highly sensitive to dieback and large populations of plants have succumbed to the disease. Collected and described by Robert Brown in the early 19th century, ''Banksia coccinea'' appears to be most closely related to ''Banksia speciosa'' and ''B. baxteri''. ''Banksia coccinea'' plants are killed by bushfire, and regenerate from seed. The flowers attract nectar- and insect-feeding birds, particularly honeyeaters, and a variety of insects. Widely considered one of the most attractive ''Banksia'' species, ''B. coccinea'' is a popular garden plant and one of the most important ''Banksia'' species for the cut flower industry; it is grown commercially in several countries including Australia, South Africa, Canada, the United States, New Zealand and Israel. In cultivation, ''B. coccinea'' grows well in a sunny location on well-drained soil, but it cannot survive in areas with humid or wet summers. ==Description== The scarlet banksia grows as an erect shrub or small tree, generally around 2–4 m (7–15 ft) tall, with little lateral spread. However, it can reach in height, particularly in the vicinity of Albany. The trunk is generally single at the base before branching, and covered with smooth grey bark that is 2–5 mm (0.1–0.2 in) thick and lacking in lenticels. Peaking in the summer months,〔 the pinkish-brown new growth is densely hairy. The oblong, cordate or obcordate leaves are long and wide, with 3–5 mm (0.1–0.2 in) long petioles. Truncate at the apex, they have dentate margins with small (1–3 mm long) teeth 3–18 mm (0.1–0.6 in) apart, separated by shallow u- or v-shaped sinuses. The upper surface is covered in fine fur when young and becomes smooth with age, while the undersurface is covered with white fur, particularly along the midrib.〔 The process of flowering takes 9–12 months; the stems begin developing microscopically in spring, with no visible evidence of flower spike development for around five months before the buds actually appear. Flower spikes are in bloom from May to December or January, peaking between July and October.〔 The distinctive inflorescences arise from the ends of one-year-old branchlets.〔 Squat and roughly cylindrical, they are high and 8–10 cm (3.1–4 in) wide. A field study on the southern sandplains revealed an average count of around 286 individual flowers on each spike. The white flower is covered in grey or pale brown fur, and there is little variation in colour. The style is generally scarlet, but can be dark red, orange or pink.〔 The perianth is long, while the style is long and strongly recurved or looped until they are released at anthesis.〔 Anthesis is acropetal, that is, the flowers open from the base up the spike to the apex.〔 The flowers of all banksias arise in a spiral pattern around the flower spike axis; however in ''Banksia coccinea'' they develop into distinctive vertical columns, which are strongly accentuated by large gaps in between.〔 Paired in columns, the red styles contrast with the grey-white perianth making a striking flower spike. The infructescence is small, with up to 20 small follicles concentrated at the lower end of the spike.〔 Each follicle is 6–8 mm (0.2–0.3 in) long, 1–2 mm (0.04–0.08 in) high, and 2–3 mm (c. 0.1 in) wide and usually opens with fire. The long seed is composed of the cuneate (wedge-shaped) seed body proper, measuring long and wide, and a papery wing. One side, termed the outer surface, is grey-black and wrinkled and the other—the inner surface—protrudes and is black and glistening. The seeds are separated by a dark brown seed separator that is roughly the same shape as the seeds with a depression where the seed body sits adjacent to it in the follicle. It measures long and wide. The dull green cotyledons of seedlings are long and wide, described by Alex George as "cuneate to obovate". Each cotyledon has a auricle at its base. The thick, smooth hypocotyl is 1 cm (0.4 in) high and 1.5 mm thick. The seedling leaves are crowded above the cotyledons and linear to spathulate in shape, with recurved and deeply serrated margins with v-shaped sinuses, almost dividing the leaves into triangular lobes. The first pair are long, with the next 2–4 leaves up to long. Successive leaves are more obovate in shape and up to long and wide. The seedling stems are covered in white hair.〔 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 coccinea」の詳細全文を読む スポンサード リンク
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