Neatorama » Blog Archive » 10 Most Magnificent Trees in the World.: "Pando [wiki] or the Trembling Giant in Utah is actually a colony of a single Quaking Aspen (Populus tremuloides) tree. All of the trees (technically, 'stems') in this colony are genetically identical (meaning, they’re exact clones of one another). In fact, they are all a part of a single living organism with an enormous underground root system.
Pando, which is Latin for 'I Spread,' is composed of about 47,000 stems spread throughout 107 acres of land. It estimated to weigh 6,600 tons, making it the heaviest known organism. Although the average age of the individual stems are 130 years, the entire organism is estimated to be about 80,000 years old!"