Sequoiadendron giganteum

Sequoiadendron giganteum
The "Grizzly Giant" tree in Mariposa Grove, Yosemite National Park
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Cupressaceae
Genus: Sequoiadendron
Species: S. giganteum
Binomial name
Sequoiadendron giganteum
(Lindl.) J.Buchh.

Sequoiadendron giganteum (giant sequoia; also known as giant redwood, Sierra redwood, Sierran redwood, Wellingtonia or simply Big Tree—a nickname 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). The common use of the name sequoia generally refers to Sequoiadendron giganteum, which occurs naturally only in groves on the western slopes of the Sierra Nevada Mountains of California.

The etymology of the genus name has been presumed—initially in The Yosemite Book by Josiah Whitney in 1868[3]—to be in honor of Sequoyah (1767–1843), who was the inventor of the Cherokee syllabary.[4] An etymological study published in 2012, however, concluded that the name was more likely to have originated from the Latin sequi (meaning to follow) since the number of seeds per cone in the newly-classified genus fell in mathematical sequence with the other four genera in the suborder.[5]

Description

Leaves of Sequoiadendron giganteum

Giant sequoias are the world's largest single trees and largest living thing by volume. Giant sequoias grow to an average height of 50–85 m (164–279 ft) and 6–8 m (20–26 ft) in diameter. Record trees have been measured to be 94.8 m (311 ft) in height. Claims of 17 m (56 ft) diameter have been touted by taking an author's writing[6] out of context, but the widest known at chest height is closer to 8.2 m (27 ft). Between 2014 and 2016, specimens of coast redwood were found to have larger trunk diameters than all known giant sequoias.[7]

The oldest known giant sequoia based on ring count is 3,500 years old. Giant Sequoias are among the oldest living things on Earth. Sequoia bark is fibrous, furrowed, and may be 90 cm (3.0 ft) thick at the base of the columnar trunk. It provides significant fire protection for the trees. The leaves are evergreen, awl-shaped, 3–6 millimetres (0.12–0.24 in) long, and arranged spirally on the shoots. The seed cones are 4–7 centimetres (1.6–2.8 in) long and mature in 18–20 months, though they typically remain green and closed for up to 20 years; each cone has 30–50 spirally arranged scales, with several seeds on each scale, giving an average of 230 seeds per cone. The seed is dark brown, 4–5 millimetres (0.16–0.20 in) long and 1 millimetre (0.039 in) broad, with a 1-millimetre (0.039 in) wide, yellow-brown wing along each side. Some seeds are shed when the cone scales shrink during hot weather in late summer, but most are liberated when the cone dries from fire heat or is damaged by insects.

Giant sequoia cones and seed

The giant sequoia regenerates by seed. Young trees start to bear cones at the age of 12 years. Trees up to about 20 years old may produce stump sprouts subsequent to injury, but unlike coast redwoods, shoots do not form on the stumps of mature trees. Giant sequoias of all ages may sprout from their boles when branches are lost to fire or breakage.

At any given time, a large tree may be expected to have about 11,000 cones. Cone production is greatest in the upper portion of the canopy. A mature giant sequoia has been estimated to disperse 300,000–400,000 seeds per year. The winged seeds may be carried up to 180 metres (590 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. Trunks of mature trees in groves are generally free of branches to a height of 20–50 metres (66–164 ft), but solitary trees will retain low branches.

Biology

Because of its size, the tree has been studied for its water pull. Water from the roots can be pushed up only a few meters by osmotic pressure but can reach extreme heights by using a system of branching capillarity (capillary action) in the tree's xylem (the water tubules) and sub-pressure from evaporating water at the leaves.[8] Sequoias supplement water from the soil with fog, taken up through air roots, at heights to where the root water cannot be pulled.[9]

Distribution

The Generals Highway passes between giant sequoias in Sequoia National Park

The natural distribution of giant sequoias is restricted to a limited area of the western Sierra Nevada, California. They occur in scattered groves, with a total of 68 groves (see list of sequoia groves for a full inventory), comprising a total area of only 144.16 km2 (35,620 acres). Nowhere does it grow in pure stands, although in a few small areas, stands do approach a pure condition. The northern two-thirds of its range, from the American River in Placer County southward to the Kings River, has only eight disjunct groves. The remaining southern groves are concentrated between the Kings River and the Deer Creek Grove in southern Tulare County. Groves range in size from 12.4 km2 (3,100 acres) with 20,000 mature trees, to small groves with only six living trees. Many are protected in Sequoia and Kings Canyon National Parks and Giant Sequoia National Monument.

The giant sequoia is usually found in a humid climate characterized by dry summers and snowy winters. Most giant sequoia groves are on granitic-based residual and alluvial soils. The elevation of the giant sequoia groves generally ranges from 1,400–2,000 m (4,600–6,600 ft) in the north, to 1,700–2,150 metres (5,580–7,050 ft) to the south. Giant sequoias generally occur on the south-facing sides of northern mountains, and on the northern faces of more southerly slopes.

High levels of reproduction are not necessary to maintain the present population levels. Few groves, however, have sufficient young trees to maintain the present density of mature giant sequoias for the future. The majority of giant sequoias are currently undergoing a gradual decline in density since European settlement.

While the present day distribution of this species is limited to a small area of California, it was once much more widely distributed in prehistoric times, and was a reasonably common species in North American and Eurasian coniferous forests until its range was greatly reduced by the last ice age. Older fossil specimens reliably identified as giant sequoia have been found in Cretaceous era sediments from a number of sites in North America and Europe, and even as far afield as New Zealand[10] and Australia.[11]

Ecology

Two giant sequoias, Sequoia National Park. Note the large fire scar at the base of the right-hand tree; fires do not typically kill the trees but do remove competing thin-barked species, and aid giant sequoia regeneration.

Giant sequoias are in many ways adapted to forest fires. Their bark is unusually fire resistant, and their cones will normally open immediately after a fire.[12] The giant sequoias are having difficulty reproducing in their original habitat (and very rarely reproduce in cultivation) due to the seeds only being able to grow successfully in full sun and in mineral-rich soils, free from competing vegetation. Although the seeds can germinate in moist needle humus in the spring, these seedlings will die as the duff dries in the summer. They therefore require periodic wildfire to clear competing vegetation and soil humus before successful regeneration can occur. Without fire, shade-loving species will crowd out young sequoia seedlings, and sequoia seeds will not germinate. When fully grown, these trees typically require large amounts of water and are therefore often concentrated near streams.

Fires also bring hot air high into the canopy via convection, which in turn dries and opens the cones. The subsequent release of large quantities of seeds coincides with the optimal postfire seedbed conditions. Loose ground ash may also act as a cover to protect the fallen seeds from ultraviolet radiation damage.

Due to fire suppression efforts and livestock grazing during the early and mid 20th century, low-intensity fires no longer occurred naturally in many groves, and still do not occur in some groves today. The suppression of fires also led to ground fuel build-up and the dense growth of fire-sensitive white fir. This increased the risk of more intense fires that can use the firs as ladders to threaten mature giant sequoia crowns. Natural fires may also be important in keeping carpenter ants in check.

In 1970, the National Park Service began controlled burns of its groves to correct these problems. Current policies also allow natural fires to burn. One of these untamed burns severely damaged the second-largest tree in the world, the Washington tree, in September 2003, 45 days after the fire started. This damage made it unable to withstand the snowstorm of January 2005, leading to the collapse of over half the trunk.

In addition to fire, two animal agents also assist giant sequoia seed release. The more significant of the two is a longhorn beetle (Phymatodes nitidus) that lays eggs on the cones, into which the larvae then bore holes. This cuts the vascular water supply to the cone scales, allowing the cones to dry and open for the seeds to fall. Cones damaged by the beetles during the summer will slowly open over the next several months. Some research indicates many cones, particularly higher in the crowns, may need to be partially dried by beetle damage before fire can fully open them. The other agent is the Douglas squirrel (Tamiasciurus douglasi) that gnaws on the fleshy green scales of younger cones. The squirrels are active year round, and some seeds are dislodged and dropped as the cone is eaten.[13]

Discovery and naming

Shortly after their discovery by Europeans, giant sequoias were subject to much exhibition

The giant sequoia was well known to Native American tribes living in its area. Native American names for the species include wawona, toos-pung-ish and hea-mi-withic, the latter two in the language of the Tule River Tribe.

The first reference to the giant sequoia by Europeans is in 1833, in the diary of the explorer J. K. Leonard; the reference does not mention any locality, but his route would have taken him through the Calaveras Grove.[14] This discovery was not publicized. The next European to see the species was John M. Wooster, who carved his initials in the bark of the 'Hercules' tree in the Calaveras Grove in 1850; again, this received no publicity. Much more publicity was given to the "discovery" by Augustus T. Dowd of the Calaveras Grove in 1852, and this is commonly cited as the species' discovery.[14] The tree found by Dowd, christened the 'Discovery Tree', was felled in 1853.

The first scientific naming of the species was by John Lindley in December 1853, who named it Wellingtonia gigantea, without realizing this was an invalid name under the botanical code as the name Wellingtonia had already been used earlier for another unrelated plant (Wellingtonia arnottiana in the family Sabiaceae). The name "Wellingtonia" has persisted in England as a common name.[15] The following year, Joseph Decaisne transferred it to the same genus as the coast redwood, naming it Sequoia gigantea, but again this name was invalid, having been applied earlier (in 1847, by Endlicher) to the coast redwood. The name Washingtonia californica was also applied to it by Winslow in 1854, though this too is invalid, belonging to the palm genus Washingtonia.

Clothespin tree in the Mariposa Grove, Yosemite National Park

In 1907, it was placed by Carl Ernst Otto Kuntze in the otherwise fossil genus Steinhauera, but doubt as to whether the giant sequoia is related to the fossil originally so named makes this name invalid.

The nomenclatural oversights were finally corrected in 1939 by J. Buchholz, who also pointed out the giant sequoia is distinct from the coast redwood at the genus level and coined the name Sequoiadendron giganteum for it.

The etymology of the genus name has been presumed—initially in The Yosemite Book by Josiah Whitney in 1868[3]—to be in honor of Sequoyah (1767–1843), who was the inventor of the Cherokee syllabary.[4] An etymological study published in 2012, however, concluded that the name was more likely to have originated from the Latin sequi (meaning to follow) since the number of seeds per cone in the newly-classified genus fell in mathematical sequence with the other four genera in the suborder.[5]

John Muir wrote of the species in about 1870:

"Do behold the King in his glory, King Sequoia! Behold! Behold! seems all I can say. Some time ago I left all for Sequoia and have been and am at his feet, fasting and praying for light, for is he not the greatest light in the woods, in the world? Where are such columns of sunshine, tangible, accessible, terrestrialized?' [16]

Uses

Wood from mature giant sequoias is highly resistant to decay, but due to being fibrous and brittle, it is generally unsuitable for construction. From the 1880s through the 1920s, logging took place in many groves in spite of marginal commercial returns. The Hume-Bennett Lumber Company was the last to harvest giant sequoia, going out of business in 1924.[17] Due to their weight and brittleness, trees would often shatter when they hit the ground, wasting much of the wood. Loggers attempted to cushion the impact by digging trenches and filling them with branches. Still, as little as 50% of the timber is estimated to have made it from groves to the mill. The wood was used mainly for shingles and fence posts, or even for matchsticks.

Pictures of the once majestic trees broken and abandoned in formerly pristine groves, and the thought of the giants put to such modest use, spurred the public outcry that caused most of the groves to be preserved as protected land. The public can visit an example of 1880s clear-cutting at Big Stump Grove near General Grant Grove. As late as the 1980s, some immature trees were logged in Sequoia National Forest, publicity of which helped lead to the creation of Giant Sequoia National Monument.

The wood from immature trees is less brittle, with recent tests on young plantation-grown trees showing it similar to coast redwood wood in quality. This is resulting in some interest in cultivating giant sequoia as a very high-yielding timber crop tree, both in California and also in parts of western Europe, where it may grow more efficiently than coast redwoods. In the northwest United States, some entrepreneurs have also begun growing giant sequoias for Christmas trees. Besides these attempts at tree farming, the principal economic uses for giant sequoia today are tourism and horticulture.

Cultivation

The well-known giant sequoia avenue planted in 1863 at Benmore Botanic Garden, Scotland. These trees are all over 50 metres (160 ft) tall.

Giant sequoia is a very popular ornamental tree in many areas. It is successfully grown in most of western and southern Europe, the Pacific Northwest of North America north to southwest British Columbia, the southern United States, southeast Australia, New Zealand and central-southern Chile. It is also grown, though less successfully, in parts of eastern North America.

Trees can withstand temperatures of −31 °C (−25 °F) or colder for short periods of time, provided the ground around the roots is insulated with either heavy snow or mulch. Outside its natural range, the foliage can suffer from damaging windburn.

A wide range of horticultural varieties have been selected, especially in Europe, including blue, compact blue, powder blue, hazel smith, pendulum—or weeping—varieties, and grafted cultivars.[18]

Europe

Sequoias in Eurodisney (near Paris) in 2009 and 2017

The giant sequoia was first brought into cultivation in Britain in 1853 by the horticulturist Patrick Matthew of Perthshire from seeds sent by his botanist son John in California.[19] A much larger shipment of seed collected from the Calaveras Grove by William Lobb, acting for the Veitch Nursery near Exeter, arrived in England in December 1853;[20] seed from this batch was widely distributed throughout Europe.

The tallest giant sequoia ever measured outside of the United States[21] is a specimen planted near Ribeauvillé in France in 1856 and measured in 2014 at a height between 57.7 m (189 ft)[22] and 58.1 m (191 ft)[23] at age 158 years.

Growth in Britain is very fast, with the tallest tree, at Benmore in southwest Scotland, reaching 56.4 m (185 ft) in 2014 at age 150 years,[24] and several others from 50–53 m (164–174 ft) tall; the stoutest is around 12 m (39 ft) in girth and 4 m (13 ft) in diameter, in Perthshire. The Royal Botanic Gardens at Kew in London also contains a large specimen. Biddulph Grange Garden in Staffordshire holds a fine collection of both Sequoiadendron Giganteum and also Sequoia sempervirens (Coast Redwood). The General Sherman of California has a volume of 1,489 m3 (52,600 cu ft); by way of comparison, the largest giant sequoias in Great Britain have volumes no greater than 90–100 m3 (3,200–3,500 cu ft), one example being the 90 m3 (3,200 cu ft) specimen in the New Forest.

Sequoiadendron giganteum at New Forest, Hampshire, England, one of the tallest in the UK at 52.73 m (173.0 ft).[25]

Numerous giant sequoia were planted in Italy from 1860 through 1905. Several regions contain specimens that range from 40 to 48 metres (131 to 157 ft) in height. The largest tree is in Roccavione, in the Piedmont, with a basal circumference of 16 metres (52 ft). One notable tree survived a 200-metre (660 ft) tall flood wave in 1963 that was caused by a landslide at Vajont Dam. There are numerous giant sequoia in parks and reserves.[26]

Growth rates in some areas of Europe are remarkable. One young tree in Italy reached 22 m (72 ft) tall and 88 cm (2.89 ft) trunk diameter in 17 years (Mitchell, 1972).

Growth further northeast in Europe is limited by winter cold. In Denmark, where extreme winters can reach −32 °C (−26 °F), the largest tree was 35 m (115 ft) tall and 1.7 m (5.6 ft) diameter in 1976 and is bigger today. One in Poland has purportedly survived temperatures down to −37 °C (−35 °F) with heavy snow cover.

Two members of the German Dendrology Society, E. J. Martin and Illa Martin, introduced the giant sequoia into German forestry at the Sequoiafarm Kaldenkirchen in 1952.[27]

Twenty-nine giant sequoias, measuring around 30 m (98 ft) in height, grow in Belgrade's municipality of Lazarevac in Serbia.[28]

The oldest sequoiadendron in the Czech Republic, at 44 m (144 ft), grows in Ratměřice u Votic castle garden.

United States and Canada

Unopened pollen (male) cones of cultivated tree in Portland, Oregon, USA (fall)
Immature seed (female) cones of cultivated tree in Portland, Oregon, USA (fall)

Giant sequoias are grown successfully in the Pacific Northwest and southern US, and less successfully in eastern North America. Giant sequoia cultivation is very successful in the Pacific Northwest from western Oregon north to southwest British Columbia, with fast growth rates. In Washington and Oregon, it is common to find giant sequoias that have been successfully planted in both urban and rural areas. In the Seattle area, large specimens exceeding 90 ft (27 m) are fairly common and exist in several city parks and many private yards (especially east Seattle including Capitol Hill, Washington Park, & Leschi/Madrona, as well as Tacoma's Jefferson Park).

In the northeastern US there has been some limited success in growing the species, but growth is much slower there, and it is prone to Cercospora and Kabatina fungal diseases due to the hot, humid summer climate there. A tree at Blithewold Gardens, in Bristol, Rhode Island is reported to be 27 metres (89 ft) tall, reportedly the tallest in the New England states.[29][30] The tree at the Tyler Arboretum in Delaware County, Pennsylvania at 29.1 metres (95 ft) may be the tallest in the northeast.[31] Specimens also grow in the Arnold Arboretum in Boston, Massachusetts (planted 1972, 18 m tall in 1998), at Longwood Gardens near Wilmington, Delaware, in the New Jersey State Botanical Garden at Skylands in Ringwood State Park, Ringwood, New Jersey, and in the Finger Lakes region of New York. Private plantings of giant sequoias around the Middle Atlantic States are not uncommon, and other publicly accessible specimens can be visited at the U.S. National Arboretum in Washington, D.C. A few trees have been established in Colorado as well.[32] Additionally, numerous sequoias have been planted with success in the state of Michigan.[33]

Sequoiadendron giganteum "Hazel Smith", photographed at the U.S. National Arboretum in September, 2014.

A cold-tolerant cultivar 'Hazel Smith' selected in about 1960 is proving more successful in the northeastern US. This clone was the sole survivor of several hundred seedlings grown at a nursery in New Jersey. The U.S. National Arboretum has a specimen grown from a cutting in 1970 that can be seen in the Gotelli Conifer Collection.

Australia

The Ballarat Botanical Gardens contain a significant collection, many of them about 150 years old. Jubilee Park and the Hepburn Mineral Springs Reserve in Daylesford, Cook Park in Orange, New South Wales and Carisbrook's Deep Creek park in Victoria both have specimens. Jamieson Township in the Victorian high country has 2 specimens which were planted in the early 1860s.[34] In Tasmania specimens are to be seen in private and public gardens, as they were popular in the mid Victorian era. The Westbury Village Green has mature specimens with more in Deloraine. The Tasmanian Arboretum contains young wild collected material. The National Arboretum Canberra has begun a grove. They also grow in the abandoned arboretum at Mount Banda Banda in New South Wales.

New Zealand

Sequoiadendron giganteum in Queenstown, New Zealand

Several impressive specimens of Sequoiadendron giganteum can be found in the South Island of New Zealand. Notable examples include a set of trees in a public park of Picton, as well as robust specimens in the public and botanical parks of Christchurch and Queenstown.[35] There is also a tree at Rangiora High School, which was planted for Queen Victoria's Golden Jubilee and is thus over 125 years old.[36]

Superlatives

Largest by trunk volume

General Sherman, largest known living single stem tree in the world

Some sequoias, such as the Mother of the Forest, were undoubtedly far larger than any living tree today. However, as of 2009, the top ten largest giant sequoias sorted by volume of their trunks are:[6][note 1]

Rank Tree Name Grove Height Girth at ground Volume
    (ft) (m) (ft) (m) (ft³) (m³)
1 General Sherman Giant Forest 274.9 83.8 102.6 31.3 52,508 1,486.9
2[note 2] General Grant General Grant Grove 268.1 81.7 107.5 32.8 46,608 1,319.8[note 2]
3[note 2] President Giant Forest 240.9 73.4 93.0 28.3 45,148 1,278.4[note 2]
4 Lincoln Giant Forest 255.8 78.0 98.3 30.0 44,471 1,259.3
5 Stagg Alder Creek Grove 243.0 74.1 109.0 33.2 42,557 1,205.1
6 Boole Converse Basin 268.8 81.9 113.0 34.4 42,472 1,202.7
7 Genesis Mountain Home Grove 253.0 77.1 85.3 26.0 41,897 1,186.4
8 Franklin Giant Forest 223.8 68.2 94.8 28.9 41,280 1,168.9
9 King Arthur Garfield Grove 270.3 82.4 104.2 31.8 40,656 1,151.2
10 Monroe Giant Forest 247.8 75.5 91.3 27.8 40,104 1,135.6

Tallest

Oldest

The Muir Snag, believed to be over 3500 years old

Greatest girth

Greatest base diameter

Greatest mean diameter at breast height

Largest limb

Thickest bark

See also

Notes

  1. ↑ The volume figures have a low degree of accuracy (at best about ±14 cubic metres or 490 cubic feet), due to difficulties in measurement; stem diameter measurements are taken at a few set heights up the trunk, and assume that the trunk is circular in cross-section, and that taper between measurement points is even. The volume measurements also do not take cavities into account. The measurements are trunk-only, and do not include the volume of wood in the branches or roots.
  2. 1 2 3 4 This table presents giant sequoias sorted by the volume of their trunks. In December 2012, Stephen Sillett announced a measurement of the President tree with a total of 54,000 cubic feet (1,500 m3) of wood and 9,000 cubic feet (250 m3) of wood in the branches.[37][38] Ranked according to the total amount of wood in the tree, the General Sherman tree is first, the President tree is second, and the General Grant tree is third.[37][38] General Sherman has 2,000 cubic feet (57 m3) more wood than the President tree.[37]

References

  1. ↑ Schmid, R. & Farjon, A. 2013. Sequoiadendron giganteum. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. <www.iucnredlist.org>. Downloaded on 13 July 2013.
  2. ↑ "Sequoia and Kings Canyon brochure" (PDF). National Park Service. Archived (PDF) from the original on 2016-10-26. Retrieved 2016-10-26.
  3. 1 2 Lowe, Gary D. (2012). "Endlicher's Sequence: The Naming of the Genus Sequoia" (PDF). cnps.org. California Native Plant Society. p. 27. Retrieved January 15, 2017. Whitney states, 'The genus was named in honor of Sequoia* or Sequoyah, a Cherokee Indian.'
  4. 1 2 Sierra Nevada - The Naturalist's Companion. University of California Press. 1 June 2000. p. 55. ISBN 978-0-520-92549-6.
  5. 1 2 Lowe, Gary D. (2012). "Endlicher's Sequence: The Naming of the Genus Sequoia" (PDF). cnps.org. California Native Plant Society. p. 33. Retrieved January 15, 2017. ...the foregoing has shown that the name of the genus Sequoia as a tribute to the Cherokee linguist Sequoyah is an unsubstantiated opinion...Endlicher named the genus for the operation that he had conducted. The new genus fell in sequence with the other four genera in his suborder.
  6. 1 2 3 4 5 6 7 8 9 10 Flint 2002
  7. ↑ Vaden, M.D. "Coast Redwood Discovery. Sequoia sempervirens".
  8. ↑ water pull at Cropsview (an agriculture science magazine) website
  9. ↑ Studies on tree height limits, and the Sequoia in particular
  10. ↑ James E Eckenwalder. Conifers of the World, The Complete Reference. p 586. Timber Press 2009. ISBN 9780881929744
  11. ↑ Bryan G Bowes. Trees and Forests, a colour guide. pp 48-49. Manson Publishing 2010. ISBN 9781840760859
  12. ↑ National Geographic Magazine December 2012
  13. ↑ Hartesveldt, RJ; Harvey, HT (1967). "The Fire Ecology of Sequoia Regeneration" (PDF). Tall Timbers Fire Ecology Conference. 7: 7.
  14. 1 2 Farquhar, Francis P. (1925). "Discovery of the Sierra Nevada". California Historical Society Quarterly. 4 (1): 3–58. doi:10.2307/25177743., Yosemite.ca.us
  15. ↑ Ornduff, R. (1994). "A Botanist's View of the Big Tree". In Aune, P. S. Proceedings of the Symposium on Giant Sequoias (PDF). US Dept. of Agriculture Forest Service (Pacific Southwest Research Station). General Technical Report PSW-GTR-151.
  16. ↑ Muir, John (November 1996). Gifford, Terry, ed. John Muir: His Life and Letters and Other Writings. Mountaineers Books. pp. 139–140. ISBN 0898864631.
  17. ↑ "Battle against Rough fire intensifies as blaze bears down on Hume Lake". fresnobee. Retrieved 2015-10-18.
  18. ↑ "Species Level Browse Results". NurseryGuide.com. Oregon Association of Nurseries. 2011. Archived from the original on 2012-03-09. Retrieved 2016-10-31.
  19. ↑ "The History of Cluny – The Plant Collectors". clunyhousegardens.com. Retrieved 23 December 2008.
  20. ↑ Christopher J. Earle. "Sequoiadendron giganteum (Lindley) Buchholz 1939". University of Hamburg. Archived from the original on 2012-07-07. Retrieved 23 December 2008.
  21. 1 2 "The thickest, tallest, and oldest giant sequoia trees (Sequoiadendron giganteum)". monumentaltrees.com. Retrieved August 2, 2015.
  22. 1 2 "Giant sequoia in the forêt domaniale de Ribeauvillé". monumentaltrees.com. Retrieved August 2, 2015.
  23. 1 2 "RIQUEWIHR/RIBEAUVILLÉ (68) : Forêt Domaniale de Ribeauvillé". Sequoias.eu. Retrieved August 2, 2015.
  24. ↑ Tree Register of the British Isles, tree-register.org
  25. ↑ "Top Trunks". Redwood World. Retrieved September 19, 2013.
  26. ↑ "Sequoie d'Italia". Retrieved January 22, 2014.
  27. ↑ Die Wiedereinführung des Mammutbaumes (Sequoiadendron giganteum) in die deutsche Forstwirtschaft. In: Mitteilungen der Deutschen Dendrologischen Gesellschaft. Vol. 75. pp. 57–75. Ulmer. Stuttgart 1984, ISBN 3-8001-8308-0
  28. ↑ Puzović, B. (August 15, 2011). "Lazarevac: Visoke sekvoje niču iz uglja" (in Serbian). Novosti.rs. Retrieved September 17, 2013.
  29. ↑ "Mansion and History". Blithewold Mansion, Gardens, and Arboretum.
  30. ↑ "Gardens". Blithewold Mansion, Gardens, and Arboretum.
  31. ↑ Big Trees Of Pennsylvania: Sequoiadendron - Giant Sequoia, pabigtrees.com
  32. ↑ "Colorado giant sequoia". giant-sequoia.com.
  33. ↑ "Michigan giant sequoia". Giant-sequoia.com.
  34. ↑ Jamieson & District Historical Society
  35. ↑ Sphaydenphotography.com
  36. ↑ Rangiora High School | History
  37. 1 2 3 Cone, Tracie (2012-12-01). "Upon further review, giant sequoia tops a neighbor". Associated Press. Archived from the original on 2012-12-02.
  38. 1 2 Quammen, David. "Giant Sequoias". National Geographic.
  39. ↑ Fry & White 1938

Sources

  • Conifer Specialist Group (1998). "Sequoiadendron giganteum". IUCN Red List of Threatened Species. Version 2006. International Union for Conservation of Nature. Retrieved 11 May 2006.  Listed as Vulnerable (VU A1cd v2.3)
  • Aune, P. S., ed. (1994). Proceedings of the Symposium on Giant Sequoias. US Dept. of Agriculture Forest Service (Pacific Southwest Research Station). General Technical Report PSW-GTR-151. 
  • Flint, W.D. (2002). To Find The Biggest Tree. Sequoia Natural History Association, Inc. ISBN 1-878441-09-4. 
  • Mitchell, Alan (1972). Conifers in the British Isles. HMSO. Forestry Commission Booklet 33. 
  • Mitchell, Alan (1996). Alan Mitchell's Trees of Britain. HarperCollins. ISBN 0-00-219972-6. 
  • Harvey, H. T.; Shellhammer, H. S.; Stecker, R. E. (1980). Giant sequoia ecology. Scientific Monograph Series. 12. Washington, DC: U.S. National Park Service. 
  • Kilgore, B. (1970). "Restoring Fire to the Sequoias". National Parks and Conservation Magazine. 44 (277): 16–22. 
  • Zsolt Debreczy; Istvan Racz (2012). Kathy Musial, ed. Conifers Around the World (1st ed.). DendroPress. p. 1089. ISBN 9632190610. 

Further reading

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