Giganteum Sequoiadendron (giant sekuoya, Sierra Redwood, Redwood Sierran, or Wellingtonia) is the only living species in the genus Sequoiadendron, and one of three types of tree species known as konifera red wood, belongs to the family Cupressaceae in the subfamily Sequoioideae, co-with Sequoia sempervirens (Coast Redwood) and Metasequoia glyptostroboides (Dawn Redwood).
A common use of "sequoia" generally refers to the name Sequoiadendron, which occurs naturally only in the garden at the western slopes of the Sierra Nevada Mountains of California.
Sequoias are the giant treesin the the world'slargest in terms of total volume ( technically,only 7 living Giant Sequoia exceed 42,500 cubic feet (1,200m3 )of Monarch Lost Coast Redwood trees ,see Biggest tree ). They grow an average height of 50-85 meters (160-279 feet) and 6-8 meters (20-26 feet) in diameter. Record trees have been measured to be 94.8 meters (311 feet) high and 17 meters (56 feet) in diameter [1] The oldest Giant Sequoia based on the number of rings. 3,500 years. Sequoia bark fibrous, furrowed, and perhaps 90 cm (3.0 feet) thick at the base of columnar trunk. It provides significant fire protection for the trees. Leaves green, awl-shaped, 3-6 mm long, and ordered spiral in bud. Seed cones 4-7 cm long and mature in 18-20 months, although they usually remain green and close to 20 years; cone each having 30-50 scales arranged spiral, with several seeds on each scale giving an average of 230 seeds per cone. Seeds dark brown, 4-5 mm and 1 mm wide, with wings 1 mm wide, yellow-brown on each side. Several seed warehouse when the cone scales shrink during hot weather in late summer, but most seeds released when the cone dries from the heat of fire or damaged by insects.Giant sequoias regenerates by seed. Trees to about 20 years to produce stump sprouts after injury. Giant sequoias of all ages can grow from the trunk when the branch long lost to fire or damage, but (like the coast redwood), mature trees do not grow from the stump is cut. Young trees start to bear cones at the age of 12 years.
At any given time, a large tree can be expected to have approximately 11,000 cones. The top of the crown of any mature Giant Sequoia has always produced a larger number of cones from the lower part. A mature giant sequoia has been estimated to disperse from 300,000 to 400,000 seeds per year. Winged seeds can be up to 180 m (600 ft) from the parent tree.
Lower branches die fairly readily from shading, but trees less than 100 years old retain most of their dead branches. Mature tree trunks in gardens are generally free branches to a height of 20-50 m, but solitary trees maintain a low branch.
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