Diameter at breast height , or DBH , is a standard method of expressing the diameter of the trunk or bole of a standing tree . DBH is one of the most common dendrometric measurements.
61-663: The General Grant tree is the largest giant sequoia ( Sequoiadendron giganteum ) in the General Grant Grove section of Kings Canyon National Park in California , and the second largest giant sequoia tree in the world after the General Sherman tree . Once thought to be well over 2,000 years old, recent estimates suggest the General Grant tree is closer to 1,650 years old. The tree also features
122-528: A paleoendemic species, they occur in scattered groves, with a total of 81 groves (see list of sequoia groves for a full inventory), comprising a total area of only 144.16 km (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
183-426: 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. The trees do not begin to bear cones until they are 12 years old. Trees may produce sprouts from their stumps subsequent to injury, until about 20 years old; however, shoots do not form on
244-399: A fire. Giant sequoias are a pioneer species , and 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
305-746: A group of giant sequoias was planted by the United States Forest Service in the San Jacinto Mountains of Southern California in the immediate aftermath of a wildfire that left the landscape barren. The giant sequoias were rediscovered in 2008 by botanist Rudolf Schmid and his daughter Mena Schmidt while hiking on Black Mountain Trail through Hall Canyon. Black Mountain Grove is home to over 150 giant sequoias, some of which stand over 6.1 m (20 ft) tall. This grove
366-581: A height of 1.4 m (4 ft 7 in), but because of much active research into allometrics that are being applied to trees and forests, the convention of 1.3 m (4.3 ft) is more appropriate . Ornamental trees are usually measured at 1.5 metres above ground. Some authors have argued that the term DBH should be abolished because the heights at which the diameter is measured are excessively variable and imprecise, and imprecise measurements could strongly influence forestry calculations such as biomass. An alternative proposed by Brokaw and Thompson (2000)
427-646: A small detachment of the Mariposa Battalion during the Mariposa War . Similar to Leonard's experience, these encounters also received no publicity. 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
488-619: A volume of 1,489 m (52,600 cu ft); by way of comparison, the largest giant sequoias in Great Britain have volumes no greater than 90–100 m (3,200–3,500 cu ft), one example being the 90 m (3,200 cu ft) specimen in the New Forest . Sequoiadendron giganteum has gained the Royal Horticultural Society 's Award of Garden Merit . An avenue of 218 giant sequoias
549-528: Is 3,200–3,266 years old based on dendrochronology . That tree has been verified to have the fourth-largest lifespan of any tree, after individuals of Great Basin bristlecone pine and alerce . Giant sequoia bark is fibrous, furrowed, and may be 90 cm (3 ft) thick at the base of the columnar trunk. The sap contains tannic acid , which provides significant protection from fire damage. The leaves are evergreen , awl-shaped, 3–6 mm ( 1 ⁄ 8 – 1 ⁄ 4 in) long, and arranged spirally on
610-429: Is D x , whereby the x indicates the exact height above the floor (and along the stem) at which the diameter is measured, e.g. D 130 denotes a diameter measured at 130 cm above the ground and along the stem . On sloping ground, the "above ground" reference point is usually taken as the highest point on the ground touching the trunk, but some use the average between the highest and lowest points of ground. If
671-551: 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 —to be in honor of Sequoyah (1767–1843), who was the inventor of the Cherokee syllabary . An etymological study published in 2012, however, concluded that the name was more likely to have originated from
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#1732787681404732-681: Is estimated to have wiped out 10-14% of the giant sequoia population, or about 7,500 to 10,600 mature trees, possibly including the King Arthur Tree , one of the tallest known sequoias. In 2021, the KNP Complex and Windy Fire added to the damage, killing an estimated 3 to 5% more of the population. Controlled burns have been effective in protecting giant sequoias. In the 2022 Washburn Fire , officials credited prescribed burns in Yosemite National Park with limiting
793-421: Is he not the greatest light in the woods, in the world? Where are such columns of sunshine, tangible, accessible, terrestrialized?' 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
854-414: Is invalid, since it was already used for the palm genus Washingtonia . 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. These nomenclatural oversights were corrected in 1939 by John Theodore Buchholz , who also pointed out the giant sequoia
915-658: 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 and Australia. In 1974,
976-551: Is not to be confused with the Black Mountain Grove in the southern Sierra. Nearby Lake Fulmor Grove is home to seven giant sequoias, the largest of which is 20 m (66 ft) tall. The two groves are located approximately 175 mi (282 km) southeast of the southernmost naturally occurring giant sequoia grove, Deer Creek Grove . It was later discovered that the United States Forest Service had planted giant sequoias across Southern California. However,
1037-509: Is the General Grant tree at 8.8 m (28.9 ft). Giant sequoias are among the oldest living organisms on Earth. The oldest known giant sequoia is 3,200–3,266 years old. Wood from mature giant sequoias is fibrous and brittle; trees would often shatter after they were felled. The wood was unsuitable for construction and instead used for fence posts or match sticks. The giant sequoia is a very popular ornamental tree in many parts of
1098-428: 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
1159-641: The Calaveras Grove by William Lobb , acting for the Veitch Nursery near Exeter , arrived in England in December 1853; seed from this batch was widely distributed throughout Europe. 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, and several others from 50–53 m (164–174 ft) tall;
1220-664: 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 km (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
1281-593: 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
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#17327876814041342-425: The Washington tree lost its crown and the hollow upper half of its trunk after a fire caused by a lightning strike. 36°44′56″N 118°58′15″W / 36.7488°N 118.9709°W / 36.7488; -118.9709 Sequoiadendron giganteum Sequoiadendron giganteum , also known as the giant sequoia , giant redwood , Sierra redwood or Wellingtonia is a coniferous tree , classified in
1403-537: The DBH point falls on a swelling in the trunk it is customary to measure the girth below the swelling at the point where the diameter is smallest. Other ambiguous settings for determining the exact place where to measure the diameter is given in Dahdouh-Guebas & Koedam (2006). The two most common instruments used to measure DBH are a girthing (or diameter) tape and calipers . A girthing tape actually measures
1464-525: 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. 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
1525-697: The US. Diameter at breast height Tree trunks are measured at the height of an adult's breast, which is defined differently in different countries and situations. In many countries, DBH is measured at approximately 1.3 m (4.3 ft) above ground. The height can make a substantial difference to the measured diameter. In the United States, DBH is typically measured at 4.5 ft (1.37 m) above ground. In some countries, such as Australia, New Zealand, Burma, India, Malaysia, and South Africa, breast height diameter has historically been measured at
1586-540: The United States is a specimen planted near Ribeauvillé in France in 1856 and measured in 2014 at a height between 57.7 m (189 ft) and 58.1 m (191 ft) at age 158 years. 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. A much larger shipment of seed collected from
1647-605: The buildup of fuel and the excessive growth of more fire-sensitive trees, like white fir , have increased the risk of devastating crown fires , which have already destroyed significant portions of the sequoia population. Many destructive wildfires have hit giant sequoia groves in recent decades, including the McNally Fire in 2002, the Rough Fire in 2015, and the Railroad Fire in 2017. The Castle Fire in 2020
1708-425: 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
1769-453: 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 leads to ground fuel build-up and the dense growth of fire-sensitive white fir , which increases 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,
1830-538: The family Cupressaceae in the subfamily Sequoioideae . Giant sequoia specimens are the most massive trees on Earth. They are native to the groves on the western slopes of the Sierra Nevada mountain range of California but have been introduced, planted, and grown around the world. The giant sequoia is listed as an endangered species by the IUCN with fewer than 80,000 remaining in its native California. The tree
1891-416: The family Sabiaceae ). The name "Wellingtonia" has persisted in England as a common name. The following year, Joseph Decaisne transferred it to the same genus as the coast redwood, naming it Sequoia gigantea , but this name was also 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; this name too
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1952-525: The fire’s intensity and sparing Mariposa Grove from major harm. Experts warn that to preserve healthy groves and prevent future destruction, the use of prescribed burns must increase significantly—by about 30 times the current levels. 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 ,
2013-441: The freshly sprouted seedlings, preventing their growth. 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
2074-480: The giant sequoia was published in 2020. The size of the giant sequoia genome is 8.125 Gbp (8.125 billion base pairs) which were assembled into eleven chromosome-scale scaffolds, the largest of any organism at the time of publication. This is the first genome sequenced in the Cupressaceae family, and it provides insights into disease resistance and survival for this robust species on a genetic basis. The genome
2135-461: The giant sequoias of Black Mountain Grove and nearby Lake Fulmor Grove are the only ones known to be reproducing and propagating free of human intervention. The conditions of the San Jacinto Mountains mimic those of the Sierra Nevada , allowing the trees to naturally propagate throughout the canyon. Giant sequoias are in many ways adapted to forest fires. Their bark is unusually fire resistant, and their cones will normally open immediately after
2196-427: The girth ( circumference ) of the tree; the girthing tape is calibrated in divisions of π centimetres (3.14159 cm). The measure assumes the trunk has a circular cross-section and gives a directly converted reading of the diameter. It is accurate for most plantation trees. Calipers consist of two parallel arms one of which is fixed and the other able to slide along a scale. Calipers are held at right-angles to
2257-531: The greatest diameter at breast height is the General Grant tree at 8.8 m (28.9 ft). Between 2014 and 2016, it is claimed that specimens of coast redwood were found to have greater trunk diameters than all known giant sequoias - though this has not been independently verified or affirmed in any academic literature. 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
2318-419: The natural cycle that once relied on periodic wildfires to release seeds and clear undergrowth. Natural wildfires historically played a key role in sequoia reproduction, releasing seeds from cones and clearing undergrowth to create the open, nutrient-rich conditions needed for seedlings. Fire suppression over the last century has disrupted this cycle, limiting reproduction in many groves. Without regular fires,
2379-566: 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. More than 30 identified species of bird have been observed living in giant sequoia groves. The genome of
2440-428: 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 sequoia groves are currently undergoing a gradual decline in density since European settlement. While the present day distribution of this species
2501-456: 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 . Giant sequoias, once primarily threatened by logging, now face their greatest danger from the absence of regular fires. Fire suppression , severe wildfires, and competition from shade-tolerant species have disrupted
General Grant (tree) - Misplaced Pages Continue
2562-540: The number of seeds per cone in the newly classified genus aligned in mathematical sequence with the other four genera in the suborder. Giant sequoia specimens are the most massive individual trees in the world. 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. The specimen known to have
2623-516: 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
2684-411: 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. The natural distribution of giant sequoias is restricted to a limited area of the western Sierra Nevada , California . As
2745-448: The shoots. The giant sequoia regenerates by seed . The seed cones are 4–7 cm ( 1 + 1 ⁄ 2 –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
2806-732: 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. The tallest giant sequoia ever measured outside of
2867-544: 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 , and in their second campus at Wakehurst, contain multiple large specimens of the species. Biddulph Grange Garden in Staffordshire holds a fine collection of both Sequoiadendron giganteum and Sequoia sempervirens (coast redwood). The General Sherman of California has
2928-418: The stumps of more 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 300,000–400,000 seeds annually. The winged seeds may fly as far as 180 m (590 ft) from
2989-435: 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. These trees require large amounts of water and are often concentrated near streams. Their growth is dependent on soil moisture. Squirrels, chipmunks, finches and sparrows consume
3050-471: The third largest footprint of any living giant sequoia, measuring 107.6 ft (32.8 m) in circumference at ground level. The tree was named in 1867 after Ulysses S. Grant , Union Army general and the 18th President of the United States (1869–1877). President Calvin Coolidge proclaimed it the "Nation's Christmas Tree " on April 28, 1926. Due in large part to its huge base, the General Grant tree
3111-495: The trunk with the arms on either side of the trunk. Precision can be improved on non-circular stems by averaging two caliper measurements taken at right-angles. Electronic calipers are also available enabling highly accurate measurements to be taken and stored for further analysis. DBH is used in estimating the amount of timber volume in a single tree or stand of trees utilising the allometric correlation between stem diameter, tree height and timber volume. It can also be used in
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#17327876814043172-422: 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. Reduction of the vascular water supply to the cone scales allows the cones to dry and open for the seeds to fall. Cones damaged by the beetles during the summer will slowly open over
3233-412: The world. The etymology of the genus name was long presumed—initially in The Yosemite Book by Josiah Whitney in 1868 —to be in honor of Sequoyah (1767–1843), who was the inventor of the Cherokee syllabary . An etymological study published in 2012 debunked that "American myth," concluding that Austrian Stephen L. Endlicher derived the name from the Latin word sequi (meaning to follow ), because
3294-470: Was cut down in 1853 and exhibited across the United States. The story of Dowd's discovery gained further notoriety following a 1859 feature in Hutchings' Illustrated California Magazine , which promoted tourism to the grove. Before Augustus T. Dowd's well-known discovery in 1852, there were three earlier encounters with giant sequoias. The first known mention of the giant sequoia by a European American
3355-602: Was found to contain over 900 complete or partial predicted NLR genes used by plants to prevent the spread of infection by microbial pathogens. The genome sequence was extracted from a single fertilized seed harvested from a 1,360-year-old tree specimen in Sequoia/Kings Canyon National Park identified as SEGI 21. It was sequenced over a three-year period by researchers at University of California, Davis , Johns Hopkins University , University of Connecticut , and Northern Arizona University and
3416-422: Was in 1833 by explorer J.K. Leonard, who recorded it in his diary. While Leonard did not specify a location, his travels likely took him through Calaveras Grove , but this observation remained unnoticed. In 1850, John M. Wooster encountered a giant sequoia at Calaveras Grove and carved his initials into the bark of the "Hercules" tree. A year later, in 1851, Robert Eccleston traveled through Nelder Grove with
3477-485: Was introduced to the U.K. in 1853, and by now might have 5,000 mature trees growing there where it is more commonly known as Wellingtonia after the Duke of Wellington. The giant sequoia 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. The specimen known to have the greatest diameter at breast height
3538-591: Was planted in 1865 near the town of Camberley , Surrey , England. The trees have since been surrounded by modern real estate development. In 2024, there were 4,949 notable sequoias in the UK, with most of these trees being mature speciments. There is uncertainty if this is an undercount or overcount of the mature trees. In addition there are an estimated 500,000 Sequoiadendron giganteum and Sequoia sempervirens that are not mature. Growing conditions are generally more conducive for these trees than in their native range in
3599-609: Was supported by grants from Save the Redwoods League and the National Institute of Food and Agriculture as part of a species conservation, restoration and management effort. The giant sequoia first gained widespread attention in 1852 when grizzly hunter Augustus T. Dowd discovered the Discovery Tree in Calaveras Grove , marking the species' first widely publicized discovery by non-natives. The tree
3660-463: Was the last to harvest giant sequoia, going out of business in 1924. 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
3721-426: Was thought to be the largest tree in the world prior to 1931, when the first precise measurements indicated that the General Sherman was slightly larger. On March 29, 1956, President Dwight D. Eisenhower declared the tree a "National Shrine", a memorial to those who died in war. It is the only living object to be so declared. In September 2003, General Grant moved up one place in the giant sequoia size rankings when
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