Pando (tree)

Pando (tree)
Pando (Latin for "I spread") is a clonal organism representing an individual male quaking aspen (Populus tremuloides) that spans 106 acres and is the largest tree by weight and land mass combined while also being the largest known aspen clone. Pando was identified as a single living organism because each of its stems possess identical genetic markers operating via a massive interconnected root system that coordinates energy production, defense and regeneration across its expanse. . While sometimes referred to as a "plant" many colloquially refer to the clone as the "Pando Tree". Located in the Fremont River Ranger District of the Fishlake National Forest along the transition zone between of the Colorado Plateau and Basin and Range in south-central Utah, United States, Pando lives within 0.43 miles from the shore of Fish Lake, the largest natural mountain freshwater lake in Utah. Pando occupies and is estimated to weigh collectively , making it the heaviest known organism.. While the General Sherman tree is the largest "single" stem tree, systems used to define the largest trees vary considerably. For example, within the United States, the Official Register of Champion Trees defines the largest trees in a species specific way, while in forestry, the largest trees are measured by the greatest volume of a single stem. While many emphasize that Pando is the largest clone tree, both Coastal and Giant Redwoods also reproduce by cloning.
A recent discovery, little is known about Pando's origins and past, while some have argued its future is also uncertain due to a combination of factors including drought, human development, grazing, and fire suppression. Friends of Pando, in collaboration with the independent scientists, community leaders, and the United States Forest Service work together to study, monitor and protect the tree . Other research groups also study and work to promote awareness and protection of Pando including Western Aspen Alliance and Grand Canyon Trust in the private sector, and Utah Department of Wildlife Resources in the governmental sector. In the late 1980's, work to remove diseased trees and promote new growth began on the yet to be named tree. In the 1990's, Fishlake National Forest undertook work to promote regeneration in the Pando using coppicing, root ripping (aka :Mechanical Stimulation), and ground fire to simultaneously remove unhealthy stems while stimulating regenerative hormones. In 1993, Fishlake National Forest began work on the "Aspen Regeneration Project", installing fences to help control deer, elk who threatened to destroy the success of those efforts. Today, 53 acres of Pando is protected by 8 foot fences to control populations of mule deer (Odocoileus hemionus), elk (Cervus canadensis) as to control human uses, such as permitted grazing by domestic cattle (Bos taurus). Regeneration rates in portions of the "Aspen Regeneration Project" show promise based on photographic evidence and repeated survey plots by land managers, scientists and conservation groups between 1993 and today. Despite this, many controversial claims have been made with a single document driving much of debate. In 2013 US Forest Service project to protect and stimulate additional portions of Pando based on the success of the 1993 program defined 400 stems (ramets) per acre as a target for a healthy and sustainable Pando, a goal that has yet to be reached. While it is possible to define expected rates of regeneration for a given aspen clone based on genetic research and laboratory studies, such work has not been undertaken with Pando.
History
The Pando tree was identified in 1976 by Jerry Kemperman and Burton Barnes. . A posthumous biography by Burton Barnes' colleague. Daniel Kashian details the tree's discovery.
Work by Fishlake National Forest to understand and protect the tree got underway in 1987. Michael Grant, Jeffrey Mitton, and Yan Linhart of the University of Colorado at Boulder re-examined the clone after Barnes and Kemperman in 1992, naming it "Pando" and claiming it to be the world's largest organism by weight. Both teams of researchers described Pando as a single male aspen based on its morphological characteristics such as leaves and root structure. Genetic sampling and analysis in 2008 by Jennifer DeWoody of the US Forest Service, Carol Rowe, Valerie Hipkins, and Karen Mock of Utah State University and the University of Southampton confirmed previous morphological analysis by Barnes, Kemperman, Mitton and Linhart and verified Pando was in fact, a clonal colony operating as a single organism. Paul Rogers and Darren McAvoy, also with Utah State University, completed an assessment of Pando's status in 2018 and stressed the importance of reducing herbivory by mule deer as critical to conserving Pando for the future. In 2019, Rogers and Jan Šebesta surveyed other vegetation within Pando besides aspen, finding additional support for their 2018 conclusion that interactions between browsing and past and ongoing management have had adverse effects on Pando's long-term resilience to change. In 2023, a team of researchers, land managers, wildlife biologists and citizen scientists groups began long term programs to monitor deer and elk usuing GPS collars and wildlife cameras to better understand and protect Pando from wildlife browsing.
While Pando is the largest known aspen clone and its age has received considerable attention, it is not the oldest known clone. Today that distinction is owed to the Jurupa Oak Clone. Many have speculated that other larger aspen clones may exists, including Barnes who in the 1976 paper that describes the yet to be named Pando tree, also described another aspen clone that spanned 80 hectares, but the location was never documented and thus, is lost to history. It is widely assumed, genetic testing will be required to verify discoveries of simlar or larger megaflora like Pando.
Statements about Pando's age vary wildly but as Pando's homeland was dominated by glacial weather patterns until around 12,000 years ago, it is unlikely that Pando's homeland would have been hospitable to the tree before that. In 2022, research by Jan Novák, Antonin Kusbach, Jan Šebesta and Paul Rogers usuing macrocharcaols indicate a stable aspen clone has been present within Pando's landmass for at least 9,000 years, but genetic testing was not conducted to confirm charcoal material was in fact, and ancient part of Pando.
Size and age
Most agree, based on Barnes work and later work that Pando encompasses , weighs and estimated or 13.2 million pounds, and has over 40,000 stems (trunks), which die individually and are replaced by new stems growing from its roots. The root system is estimated to be several thousand years old with habitat modeling suggesting a maximum age of 14,000 years. Individual aspen stems typically do not live beyond 100–130 years.
Mitton and Grant summarize the development of stems in aspen clones:
Range of age estimates
Due to the progressive replacement of stems and roots, the overall age of an aspen clone cannot be determined from tree rings. In Pando's case, ages up to 1 million years have therefore been suggested. An age of 80,000 years is often given for Pando, but this claim derives from a National Park Service web page that redacted that claim in 2023 and was inconsistent with the Forest Service's post ice-age estimate. Glaciers repeatedly formed on the Fish Lake Plateau over the past several hundred thousand years and the Fish Lake valley occupied by Pando was partially filled by ice as recently as the last glacial maximum. Ages greater than approximately 16,000 years therefore require Pando to have survived at least the Pinedale glaciation, something that appears unlikely under current genetic estimates of Pando's age and modeling of variation in Pando's local climate.
Estimates of Pando's age have also been influenced by changes in the understanding of establishment of aspen clones in western North America. Earlier sources argued germination and successful establishment of aspen on new sites was rare in the last 10,000 years and, therefore, Pando's root system was likely over 10,000 years old. More recent observations, however, have shown seedling establishment of new aspen clones is a regular occurrence and can be abundant on sites exposed by wildfire. These findings are summarized in the U.S. Forest Service's Fire Effects Information System:
Pando in Popular Culture
In 2006 the United States Postal Service published a stamp in commemoration of the aspen, calling it one of the forty "Wonders of America".
In 2013, Pando featured as the backdrop and the subject of a music video for a successful campaign led by 4th graders of nearby Monroe, Utah, United States, to have the State of Utah's Tree be changed from Colorado Spruce to the Quaking Aspen. The song was written by famed Utah songwriter Clive Romney
In 2018, the Pando Aspen Clone figures as a central figure in the life of character "Patricia Westerford" in Richard's Powers novel, "The Overstory"
A 2022 Disney film " Strange World" has a creature named "Pando" which has similarities with the actual Pando Tree
In 2022, an episode of NBC TV Show "The Blacklist" entitled "The Trembling Giant" (a nickname for Pando) features a scene where central character Raymond 'Red' Reddington details the tree's operation
In 2022, Friends of Pando published audio works by sound conservationist and artist Jeff Rice documenting the tree's subterrenean workings for the first time.
See also
Basal shoot
List of oldest trees
List of individual trees
Rhizome
Vegetative reproduction
Largest organisms
Auxin
Cytokinins
Fish Lake National Forest
References
Additional references from OECD quote in history section
External links
Pando at Atlas Obscura
Friends of Pando "A Guide to All Things Pando"
Populus
Individual trees in Utah
Fishlake National Forest
Oldest trees