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Pando, the quaking aspen -

The heaviest known single organism on Earth isn't a whale, an elephant, or even a single tree. That honor goes to Pando, a massive clonal colony of quaking aspen trees in Utah, weighing in at a mindboggling 6,000 tons.

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Pando, the quaking aspen -

What may look like a forest is actually one singular organism, connected by a vast network of underground roots that sprout up into 40,000 'individual' trees. Pando stretches over 108 acres and is thought to be 80,000 years old, making it one of the oldest living organisms on Earth.

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The honey fungus -

Another impressively massive clonal colony exists in Oregon. Mostly underground, the colony of Armillaria ostoyae, or honey fungus, is playfully referred to as the Humongous Fungus and occupies 3.5 square miles (9.1 square km) of land.

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The honey fungus -

This incredible organism only rears its head above ground in small, short clumps, but it is the largest organism on Earth by area.

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The giant sequoia -

The old-growth sequoia trees that dot the Pacific Northwest of the United States are world famous for being the largest trees on Earth. They can reach as high as 300 feet (91.5 m), with trunks as wide as 25 feet (7.6 m) in diameter.

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Phellinus ellipsoideus -

While the Phellinus ellipsoideus fungus can't hold a candle to the immensity of the underground Humongous Fungus, it does take the cake for having the largest fruiting body of any other fungus. The largest studied specimen weighs in at a whopping 1,100 pounds (500 kg).

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Hyperion the redwood -

The single tallest tree in the world also resides in the Pacific Northwest. It's a redwood named Hyperion, and stretches an incredible 380 feet (116 m) in the air.

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El Tule -

The widest tree on Earth is an old Montezuma cypress located in Oaxaca, Mexico. El Tule's trunk, including its buttressed roots, is 138 feet (42 m) in diameter.

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Dawsonia superba -

The word "moss" brings to mind soft, green fuzz on rock faces and the sides of trees, whose individual units don't reach even a centimeter off their surface. That makes the world's tallest moss, Dawsonia superba, standing at 20 inches (50 cm) high, quite a giant indeed.

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Shark Bay's giant seagrass meadow -

Just off the coast of Western Australia, in Shark Bay, resides one of the largest underwater organisms on Earth. It's a massive meadow of seagrass, that happens to be one single individual

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Shark Bay's giant seagrass meadow -

Shark Bay's massive, clonal seagrass meadow occupies a mindboggling 1,544 square miles (4,000 square km) of sea floor off the coast of Australia.

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Ibiza's Neptune grass -

The meadow in Shark Bay isn't the only massive, underground plant. Off the coast of the island of Ibiza lies a colony of Neptune grass that is possibly the oldest living organism on Earth, and certainly one of the largest.

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Ibiza's Neptune grass -

This ancient plant is estimated to be and astonishing 100,000 years old, and still going strong, covering five miles (eight km) of the Mediterranean sea floor all by itself.

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The corpse flower -

The largest flower in the world is the fascinating, but dreaded, rafflesia. Affectionately nicknamed the corpse flower, it is just as famous for its heinous smell as it is for its massive size.

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The corpse flower -

In full bloom, the corpse flower can stretch out to three feet (one meter) wide, and can weigh a hefty 20 pounds (9 kg).

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Titan arum -

The tallest flower on Earth is closely related to the corpse flower, and is nearly just as stinky. The titan arum can be found towering over its fellow plants in the Sumatra rain forests of Indonesia.

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Titan arum -

Growing straight up, the titan arum can reach a remarkable height of nearly 10 feet (three meters), although it takes this massive flower around seven years to grow to its full potential.

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Giant kelp -

Giant kelp is the largest seaweed in the world, and also the largest species of sea algae in general. These long, underwater vines grow in groups known as kelp forests, mostly up and down the west coast of the Americas.

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Giant kelp -

Giant kelp can grow to incredible lengths, stretching as long as 145 feet (45 m). Its long, leafy tendrils can create the atmosphere of a true underwater forest.

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Giant barrel sponge -

While sponges are technically animals, they are very simple animals that have more in common with vegetation than other animals at first glance. The largest species of sea sponge is the giant barrel sponge.

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Giant barrel sponge -

These massive, underwater constructions can be found in the warm waters of the Caribbean, and can grow up to six feet (two meters) tall.

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Giant Indian banyan -

There are many ways to measure the world's largest tree. When measured by the size of its canopy, the winner is the giant Indian banyan by a longshot. The largest, named Thimmamma Marrimanu, has a canopy that stretches across 4,721 acres of forest.

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Eucalyptus regnans -

The tallest flowering plant species on Earth is Eucalyptus regnans, found in Tasmania, Australia. The largest measured specimen was an impressive 330 feet (100 m) off the ground.

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Brazilian rhubarb -

With so many leafy plants populating the Earth's forests and jungles, there's a lot of competition in the battle to be the biggest. So far, the Brazilian rhubarb plant reigns supreme, with leaves that can grow to be up to 11 feet (3.3 m) wide.

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Bolivian water lily -

Lily pads, in the minds of most people, are just big enough for a frog to sit on, but the biggest species in the world is much larger. The Bolivian water lily can measure  over 10 feet (3 meters) from end to end.

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Giant viruses -

There are formidable giants even in the microscopic world of bacteria and viruses. Recent research conducted in and around melting glaciers and ice caps have uncovered a number of ancient viruses far larger than any we've seen before.

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Pithovirus -

The largest virus ever found is the Pithovirus, discovered frozen in the ice of Siberia in 2015. It measured at 1.5 micrometers long, making it dozens of times larger than the COVID-19 virus, for example.

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Pandoravirus -

The second-largest virus on record is the Pandoravirus, discovered only one year before the Pithovirus, with a length of one micrometer.

Sources: (ThoughtCo.) (Treehugger) (Scientific American)

See also: These plants and flowers can kill you

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