A thousand volunteers buried their underpants to map soil health worldwide. The results, published in Plants People Planet, reveal that soil management significantly impacts soil life and quality. Agroecologist Marcel van der Heijden said, “Healthy, biologically active soil is crucial for fertility, nutrient cycling, and many other ecosystem services.”

Soil health is vital for agriculture and food security, yet it's deteriorating globally. Decomposition rates of complex organic matter, like leaves and wood, are key indicators. The ‘teabag index’ was improved using cotton underpants, chosen for a playful citizen science approach. In the U.S. project, underpants were buried for two months and then dug up, with results showing a stark difference in decomposition rates based on soil type.

The experiment highlighted the importance of engaging the public in scientific research. It also underscored the need for better soil management to combat global decline. As van der Heijden noted, ‘Our results show that how soil is managed can significantly affect both soil life and soil quality.’

This unique method of soil analysis could lead to more widespread citizen science projects, making scientific research more accessible and engaging for the public. The underpants, once dug up, provided a tangible and humorous representation of the complex processes occurring beneath our feet.