Populus tremuloides

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Quaking aspen
2013-10-06 15 04 21 Aspens during autumn along the Changing Canyon Nature Trail in Lamoille Canyon, Nevada.jpg
Quaking aspen grove in Lamoille Canyon, Nevada, U.S.
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malpighiales
Family: Salicaceae
Genus: Populus
Section: Populus sect. Populus
Species:
P. tremuloides
Binomial name
Populus tremuloides
Populus tremuloides range map 2.png

Populus tremuloides is a deciduous tree native to cooler areas of North America, one of several species referred to by the common name aspen. It is commonly called quaking aspen, [2] [3] [4] trembling aspen, [2] [3] American aspen, [3] mountain or golden aspen, [5] trembling poplar, [5] white poplar, [5] and popple, [5] as well as others. [5] The trees have tall trunks, up to 25 metres (82 feet) tall, with smooth pale bark, scarred with black. The glossy green leaves, dull beneath, become golden to yellow, rarely red, in autumn. The species often propagates through its roots to form large clonal groves originating from a shared root system. These roots are not rhizomes, as new growth develops from adventitious buds on the parent root system (the ortet).

Contents

Populus tremuloides is the most widely distributed tree in North America, being found from Canada to central Mexico. [4] [6] It is the defining species of the aspen parkland biome in the Prairie Provinces of Canada and extreme northwest Minnesota.

Description

Aspen catkins in spring 2015-03-16 12 22 15 Aspen catkins on Idaho Street (Interstate 80 Business) in Elko, Nevada.JPG
Aspen catkins in spring
Trembling aspen bark Trembling aspen (275499901).jpg
Trembling aspen bark

The quaking aspen is a tall, fast-growing tree, usually 15–18 meters (50–60 ft) at maturity, with a trunk 25 centimeters (10 in) in diameter; [7] records are 36.5 m (119 ft 9 in) in height and 1.37 m (4 ft 6 in) in diameter. The bark is relatively smooth, whitish (light green when young), [7] and is marked by thick black horizontal scars and prominent black knots. Parallel vertical scars are tell-tale signs of elk, which strip off aspen bark with their front teeth.

The leaves on mature trees are nearly round, 4–6 cm (1+1⁄2–2+1⁄4 in) in diameter [7] with small rounded teeth, and a 3–7 cm (1+1⁄4–2+3⁄4 in) long flattened [7] petiole. The leaves are green above and gray below. [7] Young trees and root sprouts have much larger (10–20 cm, 4–8 in long), nearly triangular leaves. (Some species of Populus have petioles flattened partially along their length, while the aspens and some other poplars have them flattened from side to side along the entire length of the petiole.)

Aspens are dioecious, with separate male and female clones. The flowers are catkins 4–6 cm (1+1⁄2–2+1⁄4 in) long, produced in early spring before the leaves. The fruit is a 10 cm-long (4 in) pendulous string of 6-millimeter (1⁄4 in) capsules, each capsule containing about ten minute seeds embedded in cottony fluff, which aids wind dispersal of the seeds when they are mature in early summer. Trees as young as 2–3 years old may begin seed production, but significant output starts at 10 years of age. Best seed production is obtained between the ages of 50 and 70 years. [2]

Quaking aspen grows more slowly in the dry conditions of western North America than it does in the more humid east and also lives longer—ages of 80–100 years are typical, [7] with some individuals living 200 years; the root system can live much longer. [7] In the east, stands decay faster, sometimes in 60 years or less depending on the region.

Name

The quaking or trembling of the leaves that is referred to in the common names is due to the flexible flattened petioles. [8] The specific epithet, tremuloides, evokes this trembling behavior and can be literally translated as "like (Populus) tremula", the European trembling aspen.

Distribution

Trembling aspen at sunset in Langley, British Columbia, December 2010 Reflection of tree.JPG
Trembling aspen at sunset in Langley, British Columbia, December 2010

Quaking aspen occurs across Canada in all provinces and territories, with the possible exception of regions of Nunavut north of the James Bay islands. In the United States, it can be found as far north as the northern foothills of the Brooks Range in Alaska, where road margins and gravel pads provide islands of well-drained habitat in a region where soils are often waterlogged due to underlying permafrost. [9] It occurs at low elevations as far south as northern Nebraska and central Indiana. In the Western United States, this tree rarely survives at elevations lower than 1,500 feet (460 m) due to hot summers experienced below that elevation, and is generally found at 5,000–12,000 feet (1,500–3,700 m). [4]

It grows at high altitudes as far south as Guanajuato, Mexico. [4] It grows in isolated areas in northeastern Mexico as well as Baja California, Jalisco, the State of Mexico, Michoacán, Sinaloa, Sonora, and Veracruz. [10]

Quaking aspen grows in a wide variety of climatic conditions. January and July average temperatures range from −30 °C (−22 °F) and 16 °C (61 °F) in the Alaska Interior to −3 °C (27 °F) and 23 °C (73 °F) in Fort Wayne, Indiana. Average annual precipitation ranges from 1,020 mm (40 inches) in Gander, Newfoundland and Labrador to as little as 180 mm (7 inches) in the Alaska Interior. The southern limit of the species' range roughly follows the 24 °C (75 °F) mean July isotherm. [4]

In the sagebrush steppe, aspens occur with chokecherry, serviceberry, and hawthorn, forming a habitable haven for animal life. [11] Shrub-like dwarf clones exist in marginal environments too cold and dry to be hospitable to full-size trees, for example at the species' upper elevation limits in the White Mountains. [12]

Ecology

Clonal colonies of different autumnal colors on a mountainside in the Matanuska Valley in Alaska Quakingfallcolors.JPG
Clonal colonies of different autumnal colors on a mountainside in the Matanuska Valley in Alaska

Quaking aspen propagates itself primarily through root sprouts, and extensive clonal colonies are common. Each colony is its own clone, and all trees in the clone have identical characteristics and share a single root structure. A clone may turn color earlier or later in the fall than its neighboring aspen clones. Fall colors are usually bright tones of yellow; in some areas, red blushes may be occasionally seen. As all trees in a given clonal colony are considered part of the same organism, one clonal colony, named Pando, is considered the heaviest [13] and oldest [14] living organism on the planet. Pando spans across 43 hectares, weighs six million kilograms, most scientists agree that the Pando seed set down sometime between 8,000 and 12,000 years ago when climate currents in the region shifted at the end of the last ice age. [15] Aspens do produce seeds, but seldom grow from them. Pollination is inhibited by the fact that aspens are either male or female, and large stands are usually all clones of the same sex. Even if pollinated, the small seeds (three million per pound) are only viable a short time as they lack a stored food source or a protective coating. [16]

The buds and bark supply food for snowshoe hares, moose, black bears, cottontail rabbits, porcupines, deer, grouse, and mountain beavers. The shoots are eaten by sheep, goats, and cattle. Sheep and goats also browse the foliage, as do game animals including elk. [17] [18] Grouse and quail especially eat the buds in winter. Mammals such as beavers and rabbits eat the bark, foliage, and buds. [17] Beavers also store aspen logs for winter food. Other animals nest in aspen groves. [7] The leaves of the quaking aspen and other species in the genus Populus serve as food for caterpillars of various moths and butterflies. [19] Quaking aspen trees also serve as hosts to certain damaging insects such as the large aspen tortrix. [20]

Dieback

Typical yellow autumn foliage Populus tremuloides 8163.jpg
Typical yellow autumn foliage
Atypical orange and red autumn foliage 2014-10-05 14 33 30 Aspens showing autumn foliage coloration in Lamoille Canyon, Nevada.JPG
Atypical orange and red autumn foliage

Increased mortality in trembling aspen stands have been reported since the early 1990s across North America. [21] As this accelerated in 2004, a debate over causes began. This increased dieback has been linked to multiple stressors, such as defoliation by the forest tent caterpillar (Malacosoma disstria), wood-boring beetles such as the poplar borer (Saperda calcarata) and the bronze poplar borer (Agrilus liragus), and fungal disturbances such as those by the Cytospora canker (Valsa sordida). [22] [21]

Many areas of the Western US have experienced increased diebacks which are often attributed to ungulate grazing and wildfire suppression. At high altitudes where grasses can be rare, ungulates can browse young aspen sprouts and prevent those young trees from reaching maturity. As a result, some aspen groves close to cattle or other grazing animals, such as deer or elk, have very few young trees and can be invaded by conifers, which are not typically browsed. Another possible deterrent to aspen regeneration is widespread wildfire suppression. Aspens are vigorous resprouters and even though the above-ground portion of the organism may die in a wild-fire, the roots, which are often protected from lethal temperatures during a fire, will sprout new trees soon after a fire. Disturbances such as fires seem to be a necessary ecological event in order for aspens to compete with conifers, which tend to replace aspens over long, disturbance-free intervals. The current dieback in the American West may have roots in the strict fire suppression policy in the United States. [23] On the other hand, the widespread decimation of conifer forests by the mountain pine beetle may provide increased opportunities for aspen groves to proliferate under the right conditions. [24]

Increased mortality has also been linked in turn to climate change. Thaw-freeze events and light snowfall in late winter as a result of increased temperatures has led to increased dieback in Southern and Western Canada. [21] Furthermore, climate records show that historically, most periods of aspen decline have been paired with periods of severe drought, which has worsened in recent years due to a changing climate. [25] Many stands of aspen that have been affected by climate change in recent years have poor regeneration potential, leading to concerns of widespread loss of aspen cover in the future. [25]

Because of vegetative regeneration by aspen, where an entire group of trees are essentially clones, there is a concern that something that hits one will eventually kill all of the trees, presuming they share the same vulnerability. A conference was held in Utah in September 2006 to share notes and consider investigative methodology. [26]

Uses

Aspen bark contains a substance that was extracted by indigenous North Americans and European settlers of the western U.S. as a quinine substitute. [16]

Like other poplars, aspens make poor fuel wood, as they dry slowly, rot quickly, and do not give off much heat. Yet they are still widely used in campgrounds because they are cheap and plentiful and not widely used in building lumber. Pioneers in the North American west used them to create log cabins and dugouts, though they were not the preferred species. [27]

Aspen wood is used for pulp products [7] (its main application in Canada) such as books, newsprint, and fine printing paper. It is especially good for panel products such as oriented strand board and waferboard. It is light in weight and is used for furniture, boxes and crates, core stock in plywood, and wall panels. [28]

Culture

The quaking aspen is the state tree of Utah. [29]

See also

Related Research Articles

<i>Populus</i> Genus of plants

Populus is a genus of 25–30 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar, aspen, and cottonwood.

<i>Populus <span style="font-style:normal;">sect.</span> Populus</i> Section of plants

Populus section Populus, of the Populus (poplar) genus, includes the aspen trees and the white poplar Populus alba. The five typical aspens are all native to cold regions with cool summers, in the north of the Northern Hemisphere, extending south at high altitudes in the mountains. The White Poplar, by contrast, is native to warmer regions, with hot, dry summers. These trees are all medium-sized deciduous trees ranging 15–30 metres (49–98 ft) tall.

<span class="mw-page-title-main">Bristlecone pine</span> Three species of pine trees native to the Western United States

The term bristlecone pine covers three species of pine tree. All three species are long-lived and highly resilient to harsh weather and bad soils. One of the three species, Pinus longaeva, is among the longest-lived life forms on Earth. The oldest of this species is more than 4,800 years old, making it the oldest known individual of any species. Many scientists are curious as to why this tree is able to live so long. In one study, they discovered that Pinus longaeva has higher levels of telomerase activity, which further slows or prevents the attrition rate of telomeres. This potentially contributes to the extended life of the bristlecone pine.

<span class="mw-page-title-main">Clonal colony</span> Genetically identical, single site plants, fungi, or bacteria

A clonal colony or genet is a group of genetically identical individuals, such as plants, fungi, or bacteria, that have grown in a given location, all originating vegetatively, not sexually, from a single ancestor. In plants, an individual in such a population is referred to as a ramet. In fungi, "individuals" typically refers to the visible fruiting bodies or mushrooms that develop from a common mycelium which, although spread over a large area, is otherwise hidden in the soil. Clonal colonies are common in many plant species. Although many plants reproduce sexually through the production of seed, reproduction occurs by underground stolons or rhizomes in some plants. Above ground, these plants most often appear to be distinct individuals, but underground they remain interconnected and are all clones of the same plant. However, it is not always easy to recognize a clonal colony especially if it spreads underground and is also sexually reproducing.

<i>Larix laricina</i> Species of larch native to North America

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The balsam poplars are a group of about 10 species of poplars, indigenous to North America and eastern Asia, distinguished by the balsam scent of their buds, the whitish undersides of their leaves, and the leaf petiole being round in cross-section. They are large deciduous trees, 30–60 m tall, with leaves with a rounded base, pointed apex, and a whitish waxy coating on the underside of the leaf; this latter distinguishes them from most other poplars. The name is derived from the pleasant balsam smell of the opening buds and leaves in spring, produced by a sticky gum on the buds which also helps protect the buds from insect damage. The balsam poplars are light-demanding trees that require considerable moisture. Balsam poplars are tolerant of very cold conditions, occurring further north than other poplars except for the aspens. The poplars in Southern California are tolerant of 100 plus degree heat. They grow along dry washes and dry riverbed's. The dry washes and dry riverbeds will have flowing water when it rains sufficiently. Their leaves hang down and are at an edge to the sun. This may be another factor why they can take the high heat. Their leaves tremble in the slightest breeze like the quaking aspen

<i>Populus alba</i> Species of plant of the genus Populus

Populus alba, commonly called silver poplar, silverleaf poplar, or white poplar, is a species of poplar, most closely related to the aspens. It is native to a region spanning from the Atlas Mountains of Africa, through most of South and Central Europe, into Central Asia; it has been introduced to many temperate, moist regions worldwide. It grows in moist sites, often by watersides, in regions with hot summers and cold to mild winters.

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<i>Populus trichocarpa</i> Species of tree

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<i>Populus tremula</i> Species of plant

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<i>Melampsora medusae</i> Species of fungus

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<i>Populus grandidentata</i> Species of deciduous tree native to North America

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<span class="mw-page-title-main">Pando (tree)</span> Largest known organism

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<i>Entoleuca mammata</i> Species of fungus

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<span class="mw-page-title-main">Fire adaptations</span> Traits of plants and animals

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References

  1. ↑ Barstow, M.; Stritch, L. (2018). "Populus tremuloides". IUCN Red List of Threatened Species . 2018: e.T61960127A61960136. doi: 10.2305/IUCN.UK.2018-2.RLTS.T61960127A61960136.en . Retrieved 20 September 2021.
  2. 1 2 3 Quaking Aspen by the Bryce Canyon National Park Service
  3. 1 2 3 "Populus tremuloides". Germplasm Resources Information Network . Agricultural Research Service, United States Department of Agriculture.
  4. 1 2 3 4 5 Perala, D. A. (1990). "Populus tremuloides". In Burns, Russell M.; Honkala, Barbara H. (eds.). Hardwoods. Silvics of North America. Vol. 2. Washington, D.C.: United States Forest Service (USFS), United States Department of Agriculture (USDA) – via Southern Research Station.
  5. 1 2 3 4 5 "technology transfer fact sheet: Populus spp" (PDF). Forest Products Laboratory: R&D USDA. Madison, Wisconsin: United States Department of Agriculture Forest Service, Center for Wood Anatomy Research. Retrieved 20 September 2010.
  6. ↑ "Aspen, Quaking (Populus tremuloides)". Arbor Day Foundation.
  7. 1 2 3 4 5 6 7 8 9 Arno, Stephen F.; Hammerly, Ramona P. (2020) [1977]. Northwest Trees: Identifying & Understanding the Region's Native Trees (field guide ed.). Seattle: Mountaineers Books. pp. 203–208. ISBN   978-1-68051-329-5. OCLC   1141235469.
  8. ↑ "Populus tremuloides – Purdue Arboretum Explorer" . Retrieved 2023-11-16.
  9. ↑ Ackerman, Daniel; Breen, Amy (2016-06-06). "Infrastructure Development Accelerates Range Expansion of Trembling Aspen ( Populus tremuloides, Salicaceae) into the Arctic". Arctic. 69 (2): 130–136. doi: 10.14430/arctic4560 . ISSN   1923-1245.
  10. ↑ Hassler, Michael (3 January 2024). "World Plants". Synonymic Checklist and Distribution of the World Flora. Version 18.3. Retrieved 10 January 2024.
  11. ↑ Taylor, Ronald J. (1994) [1992]. Sagebrush Country: A Wildflower Sanctuary (rev. ed.). Missoula, MT: Mountain Press Pub. Co. p. 174. ISBN   0-87842-280-3. OCLC   25708726.
  12. ↑ Hall, Clarence A., ed. (1991). Natural history of the White-Inyo Range, eastern California. Berkeley: University of California Press. p. 91. ISBN   0-520-06895-5. OCLC   23653610.
  13. ↑ Mitton, Jeffry B.; Grant, Michael C. (1996–2001). "Genetic Variation and the Natural History of Quaking Aspen". BioScience. 46 (1): 25–31. doi:10.2307/1312652. ISSN   0006-3568. JSTOR   1312652. S2CID   87362686.
  14. ↑ Jenkins, Michael (1993-01-01). "Fire History Determination in the Mixed Conifer/Aspen Community of Bryce Canyon National Park". UW National Park Service Research Station Annual Reports. 17: 31–35. doi: 10.13001/uwnpsrc.1993.3135 . ISSN   2693-2407.
  15. ↑ Lance Oditt, Pando: Documenting a Tree That Redefines What a Tree Can Be, https://www.nationalforests.org/blog/pando-documenting-a-tree-that-redefines-what-trees-can-be
  16. 1 2 Ewing, Susan. The Great Alaska Nature Factbook. Portland: Alaska Northwest Books, 1996.
  17. 1 2 Whitney, Stephen (1985). Western Forests (The Audubon Society Nature Guides). New York: Knopf. p.  390. ISBN   0-394-73127-1.
  18. ↑ Peattie, Donald Culross (1953). A Natural History of Western Trees. New York: Bonanza Books. p. 320.
  19. ↑ Lindroth, Richard L.; St. Clair, Samuel B. (2013-07-01). "Adaptations of quaking aspen (Populus tremuloides Michx.) for defense against herbivores". Forest Ecology and Management. Resilience in Quaking Aspen: restoring ecosystem processes through applied science. 299: 14–21. doi:10.1016/j.foreco.2012.11.018. ISSN   0378-1127.
  20. ↑ Parry, Dylan (1997). The relationship between trembling aspen phenology and larval development of the large aspen tortrix. W. J. A. Volney, C. R. Currie, Northern Forestry Centre. Edmonton: Canadian Forest Service, Northern Forestry Centre. ISBN   0-662-25404-X. OCLC   36695777.
  21. 1 2 3 Hogg, E H; Brandt, James P; Kochtubajda, B (2002-05-01). "Growth and dieback of aspen forests in northwestern Alberta, Canada, in relation to climate and insects". Canadian Journal of Forest Research. 32 (5): 823–832. doi:10.1139/x01-152. ISSN   0045-5067.
  22. ↑ Worrall, James J.; Egeland, Leanne; Eager, Thomas; Mask, Roy A.; Johnson, Erik W.; Kemp, Philip A.; Shepperd, Wayne D. (2008-03-20). "Rapid mortality of Populus tremuloides in southwestern Colorado, USA". Forest Ecology and Management. 255 (3): 686–696. doi:10.1016/j.foreco.2007.09.071. ISSN   0378-1127.
  23. ↑ Haskins; et al. (2007). "Impact of fire suppression on aspen populations". Forestry and Wildlife Management. 19 (3): 54–57.
  24. ↑ Pelz, Kristen A.; Smith, Frederick W. (July 2013). "How will aspen respond to mountain pine beetle? A review of literature and discussion of knowledge gaps". Forest Ecology and Management. 299: 60–69. doi:10.1016/j.foreco.2013.01.008.
  25. 1 2 Worrall, James J.; Rehfeldt, Gerald E.; Hamann, Andreas; Hogg, Edward H.; Marchetti, Suzanne B.; Michaelian, Michael; Gray, Laura K. (2013-07-01). "Recent declines of Populus tremuloides in North America linked to climate". Forest Ecology and Management. Resilience in Quaking Aspen: restoring ecosystem processes through applied science. 299: 35–51. doi:10.1016/j.foreco.2012.12.033. ISSN   0378-1127.
  26. ↑ Kelley, Katie (26 September 2006). "Emblem of the West Is Dying, and No One Can Figure Out Why". The New York Times.
  27. ↑ https://www.fs.usda.gov/nrs/pubs/LSFES_aspen_reports/1947_lakestates_aspen_15.pdf
  28. ↑ https://www.fpl.fs.usda.gov/documnts/usda/amwood/217aspen.pdf
  29. ↑ "S.B. 41 State Tree Change". Utah State Legislature.
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