Pando is a vast quaking aspen colony in central Utah that is biologically a single male organism, made up of about 47,000 genetically identical stems connected by one root system across roughly 42.8 hectares. Widely regarded as the world’s largest tree by weight and area, and often called the heaviest known organism, it was identified as a single clone through studies beginning in 1976 and later confirmed by genetic sampling. Although individual trunks live only about 100 to 130 years, the organism renews itself by sending up new shoots, and its root system may be 9,000 to 16,000 years old. Overbrowsing, along with other pressures, has made its protection a major conservation effort.