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Pinus lambertiana
Pinus lambertiana (commonly known as the sugar pine or sugar cone pine) is the tallest and most massive pine tree and has the longest cones of any conifer. It is native to coastal and inland mountain areas along the Pacific coast of North America, as far north as Oregon and as far south as Baja California in Mexico. DescriptionGrowthThe sugar pine is the tallest and largest Pinus species, commonly growing to 40–60 meters (130–195 ft) tall, exceptionally to 82 m (269 ft) tall, with a trunk diameter of 1.2–2.5 m (3 ft 11 in – 8 ft 2 in), exceptionally 3.5 m (11 ft 6 in).[2] The tallest recorded specimen is 83.45 m (273 ft 9 in) tall, is located in Yosemite National Park, and was discovered in 2015.[3] The second tallest recorded was "Yosemite Giant", an 82.05 m (269 ft 2 in) tall specimen in Yosemite National Park, which died from a bark beetle attack in 2007. Yosemite National Park also has the third tallest, measured to 80.5 m (264 ft 1 in) tall as of June 2013; the Rim Fire affected this specimen, but it survived. The next tallest known living specimens grow in southern Oregon: one in Umpqua National Forest is 77.7 m (254 ft 11 in) tall and another in Siskiyou National Forest is 77.2 m (253 ft 3 in) tall.  The bark of Pinus lambertiana ranges from brown to purple in color and is 5–10 centimeters (2–4 in) thick.[2] The upper branches can reach out over 8 m (26 ft).[2] Like all members of the white pine group (Pinus subgenus Strobus), the leaves ("needles") grow in fascicles ("bundles") of five[2] with a deciduous sheath. They are 5–11 cm (2–4+1⁄4 in) long.[4] Sugar pine is notable for having the longest cones of any conifer, mostly 10–50 cm (4–19+3⁄4 in) long,[2][5] exceptionally to 60 cm (23+1⁄2 in) long[citation needed] (although the cones of the Coulter pine are more massive); their unripe weight of 1–2 kilograms (2.2–4.4 lb) makes them perilous projectiles when chewed off by squirrels.[2] The seeds are 1–2 cm (1⁄2–3⁄4 in) long, with a 2–3-centimeter (3⁄4–1+1⁄4-inch) long wing[5] that aids their dispersal by wind. Sugar pine never grows in pure stands, always in a mixed forest, and is shade tolerant in its youth.[6] DistributionThe sugar pine occurs in Oregon and California in the Western United States southward to Baja California, specifically in the Cascade Range, Sierra Nevada, Coast Ranges, and Sierra San Pedro Martir. It is generally more abundant towards the south and can be found between 500 and 1,500 m (1,600 and 4,900 ft) above sea level.[2] GenomeThe massive 31 gigabase mega-genome of sugar pine has been sequenced in 2016 by the large PineRefSeq consortium.[7] This makes the genome one of the largest sequenced and assembled so far.[7] The transposable elements that make up the megagenome are linked to the evolutionary change of the sugar pine. The sugar pine contains extended regions of non-coding DNA, most of which is derived from transposable elements. The genome of the sugar pine represents one extreme in all plants, with a stable diploid genome that is expanded by the proliferation of transposable elements, in contrast to the frequent polyploidization events in angiosperms.[8]  Embryonal growthIn late stage of embryonal development, the sugar pine embryo changes from a smooth and narrow paraboloid to a less symmetric structure. This configuration is caused by a transverse orientation of division planes in the upper portion of the embryo axis. The root initial zone is established, and the epicotyl develops as an anlage flanked by regions of that define the cotyledonary buttresses. At this stage, the embryo is composed of the suspensor, root initials and root cap region, hypocotyl-shoot axis, and the epicotyl. The upper (distal) portion of the embryo, which gives rise to the cotyledons and the epicotyl, is considered to be the shoot apex.[9] Shoot apexThe shoot apex has the following four zones:[10]
EtymologyNaturalist John Muir considered sugar pine to be the "king of the conifers". The common name comes from the sweet resin, which Native Americans used as a sweetener.[11] John Muir found it preferable to maple sugar.[12] It is also known as the great sugar pine. The scientific name was assigned by David Douglas in 1826,[2] in honor of his friend, a botanist friend from London: Aylmer Bourke Lambert[13]. EcologyWildlifeThe large size and high nutritional value of the sugar pine seeds are appealing to many species. Yellow pine chipmunks (Neotamias amoenus) and Steller's jays (Cyanocitta stelleri) gather and hoard sugar pine seeds. Chipmunks gather wind-dispersed seeds from the ground and store them in large amounts. Jays collect seeds by pecking the cones with their beaks and catching the seeds as they fall out. Although wind is a main dispersal agent of sugar pine seeds, animals tend to collect and store them before the wind can blow them far.[14] Black bears (Ursus americanus) feed on sugar pine seeds in the fall months within the Sierra Nevada. Both sugar pine and oak species are currently in decline, directly affecting black bear food sources within the Sierra Nevada.[15] ThreatsSugar pine trees have been impacted by the mountain pine beetle (Dendroctonus ponderosae), which is native to western North America. The beetles lay their eggs inside of the tree and inhibit the tree's ability to defend itself against invading species. Beetle infestation can also cause nutrient deficiencies that slowly weaken the tree's overall health, making pines more susceptible to other threats such as fires and white pine blister rust.[16] Blister rust can weaken the tree and enable further infestation by mountain pine beetles.[17] .jpg) The sugar pine has been severely affected by the white pine blister rust (Cronartium ribicola),[18] a fungal pathogen accidentally introduced from Europe in 1909. A high proportion of sugar pines have been killed by the blister rust, particularly in the northern part of the species' range where blister rust has been present longer. The rust has also destroyed much of the Western white pine and whitebark pine throughout their ranges.[19] The U.S. Forest Service has a program for developing rust-resistant varieties of sugar pine and western white pine. Seedlings of these trees have been introduced into the wild. The Sugar Pine Foundation in the Lake Tahoe Basin has been successful in finding resistant sugar pine seed trees. Blister rust is much less common in California, where sugar, Western white and whitebark pines still survive in great numbers.[20] The species is generally resistant to fire because of its thick bark and because it clears away competing species.[2] However, its mortality has been directly linked to drier conditions and higher temperatures. Climate change presents a threat to species health: higher temperatures can decrease resin levels within the trees, weakening defenses against pathogens. At the same time, warmer winters increase survival of pests and pathogens. The weakened or dying trees then provide fuel for forest fires, which may become more frequent and more intense with rising summer temperatures, particularly if coupled with drier conditions and stronger winds.[21] Protective effortsSugar pine trees are in slow decline due to several threats: white pine blister rust, mountain pine beetles, and climate change. Efforts to restore sugar pines and other white pine trees that have been impacted by invasive species, climate change, and fires have been undertaken by governmental and non-governmental entities. One nonprofit, the Sugar Pine Foundation, was created in 2004 to plant sugar pine seeds in the Sierra Nevada along the border of California and Nevada.[20] They plant seedlings grown from seeds collected from tree strains resistant to blister rust. The foundation's aim is to build a wild a sugar pine population that is resistant to white pine rust.[22] Uses According to David Douglas, who was guided to the (exceptionally thick) tree specimen he was looking for by a Native American,[2] some tribes ate the sweetish seeds. These were eaten raw and roasted, and also used to make flour or pulverized into a spread.[2] Native Americans also ate the inner bark.[2] The sweet sap or pitch was consumed, in small quantities due to its laxative properties,[23] but could also be chewed as gum.[2] Its flavor is thought largely to be derived from the pinitol it contains.[2] In the mid-19th century, the trees were used liberally as lumber during the California Gold Rush. In modern times they are used in much lower quantities, being spared for high-end products as with Western white pine.[2] The odorless wood is also preferred for packing fruit, as well as storing drugs and other goods. Its straight grain also makes it a useful organ pipe material.[23] The wood was also long used for piano keys; in 1907 or 1908 the Connection piano-action maker Pratt, Read & Co. purchased "950,000 feet of clear sugar pine" for that use in & around Placerville, CA.[24] FolkloreIn the Achomawi creation myth, Annikadel, the creator, makes one of the 'First People' by intentionally dropping a sugar pine seed in a place where it can grow. One of the descendants in this ancestry is Sugarpine-Cone man, who has a handsome son named Ahsoballache.[25] After Ahsoballache marries the daughter of To'kis the Chipmunk-woman, his grandfather insists that the new couple have a child. To this end, the grandfather breaks open a scale from a sugar pine cone, and secretly instructs Ahsoballache to immerse the scale's contents in spring water, then hide them inside a covered basket. Ahsoballache performs the tasks that night; at the next dawn, he and his wife discover the infant Edechewe near their bed.[25] The Washo language has a word for sugar pine, simt'á:gɨm, and also a word for "sugar pine sugar", nanómba. References
Further reading
External links Wikimedia Commons has media related to Pinus lambertiana.
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