Drunken trees

Not to be confused with the floss silk tree, also known as the drunken tree or palo borracho.
A drunken forest in Siberia caused by melting permafrost

Drunken trees, tilted trees, or a drunken forest, is a stand of trees rotated from their normal vertical alignment.[1][2]

This most commonly occurs in northern subarctic taiga forests of black spruce (Picea mariana) under which discontinuous permafrost or ice wedges have melted,[3][4] causing trees to tilt at various angles.[5][6]

Tilted trees may also be caused by frost heaving,[7] and subsequent palsa development,[8] hummocks,[9] earthflows,[10][11] forested active rock glaciers,[12] landslides, or earthquakes.[13] In stands of spruce trees of equal age that germinated in the permafrost active layer after a fire, tilting begins when the trees are 50 to 100 years old, suggesting that surface heaving from new permafrost aggradation can also create drunken forests.[4]

  1. ^ Stevens, William K. (1998-08-18). "Dead Trees and Shriveling Glaciers as Alaska Melts". The New York Times. Retrieved 2007-12-19. Here and there, roadside utility poles destabilized by the melting tilt at crazy angles. So do trees, creating a phenomenon known as drunken forest.
  2. ^ de Villiers, Marq (2001). Water: The Fate of Our Most Precious Resource. Boston: Mariner Books. ISBN 978-0-618-12744-3. …caused what the locals call "drunken forests," the trees tilting and leaning…
  3. ^ Kolbert, Elizabeth (2005). "The Climate Of Man—ii" (PDF). The New Yorker. Archived from the original (PDF) on 2008-09-06. Retrieved 2007-12-17. Romanovsky pointed out a long trench running into the woods. The trench, he explained, had been formed when a wedge of underground ice had melted. The spruce trees that had been growing next to it, or perhaps on top of it, were now listing at odd angles, as if in a gale. Locally, such trees are called "drunken."
  4. ^ a b Kokelj, S.V.; Burn, C.R. (2003). "Tilt of Spruce Trees near Ice Wedges, Mackenzie Delta, Northwest Territories, Canada". In Phillips, Marcia; Springman, Sarah M.; Arenson, Lukas U. (eds.). Permafrost—Proc. 8th Int Conf. Permafrost. Rotterdam: A.A. Balkema. pp. 567–570. ISBN 978-90-5809-582-4. This observation suggests that aggradational ice development associated with post-fire active-layer thinning causes the overlying ground to heave … forests with tilted trees were underlain by permafrost of high ice content and forests with straight trees were underlain by ice-poor permafrost.
  5. ^ Ranson, Jon (2007-08-01). "Science Blog - Expedition to Siberia". Siberia Blog. NASA Earth Observatory. Archived from the original on 2007-08-08. Retrieved 2007-12-19. Permafrost that has not melted provides a solid foundation that holds trees upright. When permafrost melts, as it has here, the layer of loose soil deepens and trees lose their foundations, tipping over at odd angles.
  6. ^ Crum, Howard Alvin (1988). A Focus on Peatlands and Peat Mosses (Great Lakes Environment). University of Michigan. p. 278. ISBN 978-0-472-06378-9. drunken forest A stand of black spruce in subarctic regions of discontinuous permafrost … where the ice core melts causing trees to lean or fall
  7. ^ Pielou, E.C. (1991). After the Ice Age: the return of life to glaciated North America. Chicago, Illinois: University of Chicago Press. p. 84. ISBN 978-0-226-66812-3. The occasional groups of stunted trees that do manage to establish themselves often form a "drunken forest"; their trunks lean in all directions because frost-heaving takes place and the rising mounds of freezing soil tilt the trees growing on them.
  8. ^ Scott, Peter A.; Hansell, Roger I.C.; Erickson, William R. (1993). "Influences of wind and snow on northern tree-line environments at Churchill, Manitoba, Canada" (PDF). Arctic. 46 (4): 316–323. doi:10.14430/arctic1359. Archived from the original (PDF) on 2011-05-24. Retrieved 2007-12-19. Such trees develop in association with frost heaving and subsequent palsa development, resulting in "drunken forests"
  9. ^ Zoltai, S.C. (1975). "Tree Ring Record of Soil Movements on Permafrost". Arctic and Alpine Research. 7 (4): 331–340. doi:10.2307/1550177. JSTOR 1550177. Trees growing on hummocky permafrost terrain are subject to periodic tilting, and this tilting is recorded as compression wood.
  10. ^ ""Drunken Forest" in Colorado". Incorporated Research Institutions for Seismology. Archived from the original on 2008-07-23. Retrieved 2007-12-16. Photo showing tilted trees in the "drunken forest". The trees grow atop the Slumgullion earthflow, which is four miles long and 2000 feet wide, near Lake City, CO.
  11. ^ Wicander, Reed; Monroe, James S. (2004). Physical Geology : Exploring the Earth (with PhysicalGeologyNow and InfoTrac). Pacific Grove: Brooks Cole. p. 419. ISBN 978-0-534-39987-0. Slow mass movements advance at an imperceptible mate and are usually detectable only by the effects of their movement, such as tilted trees and power poles…
  12. ^ van Everdingen, Robert (2005). "drunken forest". Multi-language glossary of permafrost and related ground-ice terms. Boulder, Colorado: National Snow and Ice Data Center/World Data Center for Glaciology. Archived from the original on 2007-12-26. Active, forested rock glaciers may also exhibit this phenomenon due to differential movements.
  13. ^ Rozell, Ned (1995-09-21). "Formerly Frosty Footing Causes Drunken Forests, Alaska Science Forum". Geophysical Institute, University of Alaska Fairbanks. Archived from the original on 2007-12-27. Retrieved 2007-12-16. Melting permafrost is the most common cause of the drunken forest.… Landslides and earthquakes also can create drunken forests,…