Global Map Uncovers Vast Underground Fungal Networks Spanning Earth

WHO:

Live Science - Justin Stewart, an evolutionary biologist at the Society for the Protection of Underground Networks, is the first author of the study.

Live Science - Andrea Genre, an expert in arbuscular mycorrhizal fungi at the University of Turin in Italy, commented on the research.

Live Science - Edouard Evangelisti, a plant scientist at Côte d'Azur University in France, also commented on the research.

WHAT:

Live Science - A new study reveals that Earth's underground fungal network, if placed in a straight line, would span roughly 10% of the Milky Way.

Live Science - The study published in the journal Science presents the first global map of arbuscular mycorrhizal fungal networks.

Live Science - The top 6 inches (15 centimeters) of soil in high-altitude or flooded grasslands contains around 40% of the global fungal biomass.

Live Science - The average hyphal density in land topsoil is 237 feet per cubic inch (4.4 meters per cubic cm).

Live Science - The researchers estimate that if all hyphae were laid out in a straight line, they would span approximately 68 quadrillion miles (110 quadrillion km).

Live Science - The map indicates that wild grasslands have the highest density of hyphae at 355 feet per cubic inch (6.6 meters per cubic cm), while cultivated trees have the lowest at 204 feet per cubic inch (3.8 meters per cubic cm).

Live Science - The fungi are estimated to take in around 4.3 billion tons (3.9 billion metric tons) of carbon dioxide equivalent each year.

WHERE:

Live Science - The study includes data from 16,669 soil cores collected in 322 previous studies across every continent and nine biomes.

Live Science - High-altitude or flooded grasslands, such as the Everglades in Florida, are highlighted as areas with dense fungal networks.

WHEN:

Live Science - The study was published on June 11 in the journal Science.

Live Science - The researchers plan to update the map within the next five years.

WHY:

Live Science - The research aims to inform strategies for biodiversity conservation, agricultural management, and climate change mitigation.

Live Science - The study emphasizes the importance of protecting wild grasslands, which are rapidly disappearing.

HOW:

Live Science - The researchers compiled data from soil cores and used artificial intelligence to predict the distribution of arbuscular mycorrhizal fungi for every 0.4 square miles (1 square kilometer) of topsoil worldwide.

Live Science - The study analyzed hyphal density from both field studies and experiments in pots.

(UPDATED June 12, 2026 04:27 UTC)

A groundbreaking study published in the journal Science reveals that Earth's underground fungal network, if laid out in a straight line, would stretch approximately 68 quadrillion miles, which is about 10% of the Milky Way. The research, led by Justin Stewart from the Society for the Protection of Underground Networks, highlights that the top six inches of soil in high-altitude or flooded grasslands, like the Everglades, contains around 40% of the global fungal biomass, with wild grasslands showcasing the highest density of hyphae. Researchers plan to update this global map of arbuscular mycorrhizal fungal networks within the next five years, aiming to enhance strategies for biodiversity conservation and climate change mitigation.