Whales, redwood trees, and elephants are all very big — but they're not the largest living organism on the planet by acreage. That title, when looking at sheer size — the Pando tree colony holds the title of the largest living organism by mass — goes to the Armillaria Ostoyae mushroom.
Nicknamed the Humongous Fungus, this mushroom has spread across 2,385 acres of Malheur National Forest in Oregon. The scientists who discovered the fungus in 2017 used DNA testing to determine that all parts of the growth are in fact different segments of the same organism.
The giant mushroom has probably been growing for between 2,400 to 8,650 years, and its caps are said to be quite delicious.