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''Alloxylon flammeum'', commonly known as the Queensland tree waratah or red silky oak, is a medium-sized tree of the family Proteaceae found in the Queensland tropical rain forests of northeastern Australia. It has shiny green elliptical leaves up to 18 cm (7.2 in) long, and prominent orange-red inflorescences that appear from August to October, followed by rectangular woody seed pods that ripen in February and March. Juvenile plants have large (up to 25 cm (10 in) long) deeply lobed pinnate leaves. Previously known as ''Oreocallis wickhamii'', the initial specimen turned out to be a different species to the one cultivated and hence a new scientific name was required. Described formally by Peter Weston and Mike Crisp in 1991, ''A. flammeum'' was designated the type species of the genus ''Alloxylon''. This genus contains the four species previously classified in ''Oreocallis'' that are found in Australasia. ''Alloxylon flammeum'' is a canopy or emergent tree of the Mabi rainforest community of north Queensland. Its terminal tubular flowers indicate that the species is pollinated by birds. Readily adaptable to cultivation, ''Alloxylon flammeum'' prefers a site with good drainage and responds well to extra moisture and fertilisers low in phosphorus. It is listed nationally as ''vulnerable'' under the Australian Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) as most of its habitat has been cleared for agriculture and logging. == Description == In nature, this is a rainforest tree that can reach 33 m (108 ft) in height with a diameter at breast height (dbh) of 0.6 m (24 in), although in cultivation 10 m (35 ft) is more likely. The trunk has light grey bark with brown lenticels. New branchlets and leaves are hairy. The green foliage consists of several distinct juvenile and adult leaf forms, which are arranged alternately along the stems.〔 Very young plants begin with their first two to four leaves having two or three lobes, but then have narrow elliptic leaves with entire margins, measuring 6.5 to 18 cm (2.6–7.2 in) long and 1.3–2.2 cm (0.5–0.8 in) wide. These are then succeeded by pinnate juvenile leaves that have two to nine lobes arising at 30 to 40 degrees forwards, and reach 50 cm (20 in) long. They have prominent midveins along the midline of the main leaf and the lobes. The elliptic or obovate (egg-shaped) adult leaves are 8–25 cm (3.2–10 in) long and up to 4.5 cm (1.8 in) wide, and sit on 1.5 to 2.5-cm (0.6–1 in) long petioles. Occurring in spring (August to October), the bright red or orange-red inflorescences are terminal and well displayed, and consist of anywhere from 10 to 52 individual flowers split into smaller groups of 2 to 20 flowers, arranged in a corymb.〔 The flowers sit atop stalks (known as pedicels) up to 3.5 cm (1.6 in) in length, which arise in pairs off main horizontal stalks within the inflorescence. Each flower consists of a tubular perianth up to 4 cm (1.8 in) long, which partly splits along one side at anthesis to release the thick style. The stigma is contained within a slanting disc-like structure at the tip of the style. The tubular perianth splits into four segments at its tip, and the anther lies in the concave parts within each of these segments.〔 The pedicel and the outer surface of the perianth are pubescent (covered in short fine fur). Flowers are followed by woody rectangular seed pods that sit on long stalks,〔 and are 7–10 cm (2.8–4 in) long.〔 Each pod contains 8 to 10 seeds,〔 and is ripe in February and March. Each seed is separated from the others by a membranous separator, and has a long rectangular wing, which is much longer than the seed itself. The seedlings have obovate cotyledons that are 0.8–1 cm (0.3–0.4 in) wide by 1 cm (0.4 in) long.〔 ''Alloxylon flammeum'' can be distinguished from the co-occurring ''Alloxylon wickhamii'' by its hairy stems and petioles.〔 It also has brighter flowers than the latter species.〔 The New Guinean species ''A. brachycarpum'' resembles ''A. flammeum'' but has duller flowers, leaves that are shorter and wider, and fewer hairs on its perianth.〔 ''A. pinnatum'' has pinnate (lobed) adult leaves and larger inflorescences made up of 50 to 140 individual flowers. It also has crimson pollen rather than the yellow of ''A. flammeum''.〔 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「Alloxylon flammeum」の詳細全文を読む スポンサード リンク
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