A hidden fungal network longer than the distance to the Sun wraps the roots of 70% of Earth's plants, and the first global map finds it densest not under rainforests but wild grasslands

Key Points:

• Researchers have created the first global map of the underground mycorrhizal fungi network, which consists of microscopic threads called hyphae that wrap around plant roots and extend throughout the world's topsoil.
• The total length of these fungal threads is estimated at 68 quadrillion miles, nearly a billion times the Earth-Sun distance, with a teaspoon of soil containing up to 32 feet of thread; collectively, the fungi weigh four to six times as much as all humans.
• The mapping was achieved by analyzing over 16,000 soil samples from more than 300 studies worldwide, combined with a computer model incorporating climate, soil chemistry, and vegetation data, and validated by direct observation of living fungi.
• The densest fungal networks were surprisingly found under wild grasslands, which hold about 40% of the fungal life, while farmland showed roughly half the fungal density of untouched land, likely due to plowing, fertilizer, or fungicide use.
• This new map enables conservationists and farmers to identify and protect critical fungal habitats, promote sustainable farming practices, and integrate fungi into climate and conservation strategies, addressing a previously overlooked component of Earth's ecosystem.