The discovery of this new species in the central provinces of China, then recognized to belong to a genus extinct since millions of years, is considered as one of the most impostant botanical discoveries of the XX century. It reproduces by cutting, taken from young plants, and more quickly by seed, that does not need any cold stratification, placed on draining organic soil maintained constantly humid and covered by a thin layer of siliceous sand, with germination times of about one week. Obovate pale brown seeds, flattened, winged, 5-6 mm long and 4-5 mm broad. Terminal female cones, on a woody hanging lateral small branch about 3 cm long, initially ellipsoidal, about 9 mm long and of 5 mm of diameter, of green colour, globose when ripe, 1,4-2,5 cm long and of 1,6-2,3 cm of diameter, of blackish purple colour, formed by 20-30 pairs of scales perpendicular to each other (decussate), containing (2)-5-9 ovules, but the 2-3 basal couples and the three apical ones which are sterile. Numerous male cones, arranged in racemes or panicles 20-25 cm long, ovoidal, 2,5-5,5 mm long and of 2-4 mm of diameter, with ovate or obovate scales 4 mm long and 3 mm broad. In summer, on the persistent secondary branches, at the base of the junction of the deciduous small branches, develop the cones. The Metasequoia glyptostroboides Hu & W.C.Cheng (1948) is a monoecious, deciduous tree, 30-50 m tall with a diameter, at 1,5 m from the soil, up to 2,5 m, provided at the base of tabular roots (flattened roots similar to buttresses), with crown initially conical, then almost cylindrical, and brown-orange bark in the young plants tending with the time to turn dark reddish brown and to crake and flake.Īscending main branches, persistent secondary ones with alternate leaves and opposite small branches, hanging, deciduous, 5-15 cm long, in their turn provided of 20-40 pairs of opposite leaves, distichous, morbid, spaced 2-5 mm, linear with obtuse apex, 8-20 mm long and 1-2 mm broad, of bluish green or yellowish green colour more intense above, that in autumn turn red or orange before falling together with the small branches. (1847) the specific name is the combination of the name of the genus Glyptostrobus and of the Greek suffix “-οειδής” (-oeidés), from “εἶδος“ (êidos) = shape, look, hence resembling.Ĭommon names: dawn redwood, dinosaur-age tree, living fossil, water fir (English) shui shan (Chinese) abete d’acqua (Italian) secuoya de hojas caedizas (Spanish). The name of the genus is the combination of the Greek prefix “μετά” (meta), with the meaning of alike, similar, and Sequoia Endl. The species is native to China (Chongqing, Hibei and Hunan) where it lives in the mesophyllic mixed forest in the bottom of the valleys and in the ravines at the margins of water streams, on slightly acidic to neutral soils, between 7 m of altitude. The crown of the Metasequoia glyptostroboides, conical before, then cylindrical, may reach the 50 m © Giuseppe Mazza
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