Sequoiadendron giganteum

Sequoiadendron giganteum
Grizzly Giant Mariposa Grove.jpg
The "Grizzly Giant" in the Mariposa Grove, Yosemite National Park
Scientific classification edit
Kingdom:Plantae
Clade:Tracheophytes
Division:Pinophyta
Class:Pinopsida
Order:Pinales
Family:Cupressaceae
Genus:Sequoiadendron
Species:
S. giganteum
Binomial name
Sequoiadendron giganteum
Sequoia Sequoiadendron range map.png
Natural range of the California members of the subfamily Sequoioideae
red - Sequoiadendron giganteum

Sequoiadendron giganteum (giant sequoia; also known as giant redwood, Sierra redwood, Sierran redwood, Wellingtonia or simply big tree—a nickname also used by John Muir[2]) is the sole living species in the genus Sequoiadendron, and one of three species of coniferous trees known as redwoods, classified in the family Cupressaceae in the subfamily Sequoioideae, together with Sequoia sempervirens (coast redwood) and Metasequoia glyptostroboides (dawn redwood). Giant sequoia specimens are the most massive trees on Earth.[3] The common use of the name sequoia usually refers to Sequoiadendron giganteum, which occurs naturally only in groves on the western slopes of the Sierra Nevada Mountains of California. The oldest known giant sequoia is 3,200-3,266 years old

The etymology of the genus name has been presumed—initially in The Yosemite Book by Josiah Whitney in 1868[4]—to be in honor of Sequoyah (1767–1843), who was the inventor of the Cherokee syllabary.[5] An etymological study published in 2012 concluded that Austrian Stephen L. Endlicher is actually responsible for the name. A linguist and botanist, Endlicher corresponded with experts in the Cherokee language including Sequoyah, whom he admired. He also realized that coincidentally the genus could be described in Latin as sequi (meaning to follow) because the number of seeds per cone in the newly-classified genus fell in mathematical sequence with the other four genera in the suborder. Endlicher thus coined the name "Sequoia" as both a description of the tree's genus and an honor to the indigenous man he admired.[6]

Description

Leaves of S. giganteum

Giant sequoia specimens are the most massive individual trees in the world.[3] They grow to an average height of 50–85 m (164–279 ft) with trunk diameters ranging from 6–8 m (20–26 ft). Record trees have been measured at 94.8 m (311 ft) tall. Trunk diameters of 17 m (56 ft) have been claimed via research figures taken out of context.[7] The specimen known to have the greatest diameter at breast height is the General Grant tree at 8.8 m (28.9 ft).[8] Between 2014 and 2016, specimens of coast redwood were found to have greater trunk diameters than all known giant sequoias.[9] The trunks of coast redwoods taper at lower heights than those of giant sequoias which have more columnar trunks that maintain larger diameters to greater heights.

The oldest known giant sequoia is 3,200-3,266 years old based on dendrochronology.[10][11] Giant sequoias are among the oldest living organisms on Earth. Giant sequoia bark is fibrous, furrowed, and may be 90 cm (3 ft) thick at the base of the columnar trunk. The bark provides significant protection from fire damage. The leaves are evergreen, awl-shaped, 3–6 mm (1814 in) long, and arranged spirally on the shoots.

Giant sequoia cones and seed

The giant sequoia regenerates by seed. The seed cones are 4–7 cm (1 12–3 in) long and mature in 18–20 months, though they typically remain green and closed for as long as 20 years. Each cone has 30–50 spirally arranged scales, with several seeds on each scale, giving an average of 230 seeds per cone. Seeds are dark brown, 4–5 mm (0.16–0.20 in) long, and 1 mm (0.04 in) broad, with a 1-millimeter (0.04 in) wide, yellow-brown wing along each side. Some seeds shed when the cone scales shrink during hot weather in late summer, but most are liberated by insect damage or when the cone dries from the heat of fire. Young trees start to bear cones after 12 years.

Trees may produce sprouts from their stumps subsequent to injury, until about 20 years old; however, shoots do not form on the stumps of mature trees as they do on coast redwoods. Giant sequoias of all ages may sprout from their boles when branches are lost to fire or breakage.

A large tree may have as many as 11,000 cones. Cone production is greatest in the upper portion of the canopy. A mature giant sequoia disperses an estimated 300–400 thousand seeds annually. The winged seeds may fly as far as 180 m (590 ft) from the parent tree.

Lower branches die readily from being shaded, but trees younger than 100 years retain most of their dead branches. Trunks of mature trees in groves are generally free of branches to a height of 20–50 m (70–160 ft), but solitary trees retain lower branches.

Other Languages
беларуская: Секвоядэндран
Cymraeg: Welingtonia
dansk: Mammuttræ
dolnoserbski: Wjelicki mamutowy bom
eesti: Mammutipuu
Esperanto: Sekvojadendro
فارسی: درخت غول
français: Séquoia géant
한국어: 거삼나무
hornjoserbsce: Hoberski žerowc
Ido: Sequoyo
кырык мары: Секвойядендрон
македонски: Џиновска секвоја
Nederlands: Mammoetboom
norsk: Mammuttre
Перем Коми: Секвойядендрон
Piemontèis: Sequoia giganteum
português: Sequoia-gigante
සිංහල: Sequoiadendron giganteum
slovenčina: Sekvojovec mamutí
slovenščina: Mamutovec
српски / srpski: Џиновска секвоја
svenska: Mammutträd
українська: Секвоядендрон
Tiếng Việt: Cự sam
West-Vlams: Mammoetbôom
粵語: 北美巨杉
中文: 巨杉