It is a clonal colony of an individual male quaking aspen (Populus tremuloides) determined to be a single living organism by identical genetic markers.
There are about 47,000 quaking aspen steams. The older steams are almost all between 110 and 130 years old, which is about the typical life span of individual quaking aspen stems
Quaking aspens are among the most peculiar of trees. They usually reproduce asexually from an underground root system. Each stem belongs to that single root system, and aspen groves are rarely made up of genetic individuals.
It’s not clear why and how this specific grove of quaking aspens grew to be so large.
Pando occupies 43 hectares (106 acres) and is estimated to weigh collectively 6,000,000 kilograms (6,600 short tons), making it the heaviest known organism.
The root system of Pando, at an estimated 80,000 years old, is among the oldest known living organisms.
Its massive size, weight, and prehistoric age have caused worldwide fame.
Burton V Barnes, a botanical researcher, came across Pando in 1968 and was the first researcher to discover that it wasn’t a grove of different trees but, in fact, a single tree with all the stems displaying the same morphological characteristics.
The tree received its name Pando from the University of Colorado’s researcher, Michael Grant, who, in 1992, called it the world’s largest living organism.
“Pando” is a Latin word that translates to “I spread out.”
The quaking aspen is named for its leaves, which stir easily in even a gentle breeze and produce a fluttering sound with only the slightest provocation.
Pando is located in the Fremont River Ranger District of the Fishlake National Forest at the western edge of the Colorado Plateau in south-central Utah.
A study published in October 2018 concludes that Pando has not been growing for the past 30–40 years. Human interference was named as the primary cause, with the study specifically citing people allowing cattle and deer populations to thrive, their grazing resulting in fewer saplings and dying trees.
There are ways that humans can intervene to give Pando the time it needs to get back on track, among them culling voracious deer and putting up better fencing to keep the animals away from saplings.
In 2006 the US Postal Service honored Pando as one of the “40 Wonders of America” with a stamp in its commemoration.