PHOTO: Soil scientist Dr Oliver Knox examines the remains of cotton underwear that was buried to examine soil health.

In the name of soil health, used underwear is being buried in schools, backyards and fields to investigate near invisible microbial activity beneath the surface we stand on.

The project, Soil Your Undies is a joint project with the University of New England’s Cotton Hub and CottonInfo, the Australian cotton industry’s extension program.

The experiment involves burying 100 per cent cotton underwear about 5cm into the soil and leaving them for eight weeks before digging them back up.

Depending on how much, or little of the underpants remain, speaks to the health properties of the soil says UNE lecturer, Dr Oliver Knox.

The less material remaining, the healthier the soil.

“This is an awesome, engaging way to investigate the fantastic life that’s invisible in our soil,” Dr Knox said.

“You take something very visible to everyone – the undies – and by making it invisible, you investigate the invisible life.”

Dr Knox says cotton strips have been used to investigate the environment since the 1940s, which is where the project developed from, but the underwear concept makes it engaging for the education sector.

PHOTO: Soil scientist Dr Oliver Knox talks at the Sydney Royal Show about soil health and the soil your undies project.

Soil Your Undies began five years ago, and is so innovative, it’s become a Citizen Science project. CottonInfo has been supplying 100 per cent cotton underwear for the experiment.

While there are high-tech methods to measure soil health, Soil Your Undies is proving that innovation can also be simple. CottonInfo is also tracking where the jocks are buried, and what state they’re in.

“Farmers have always been accepting that their soils are an important commodity, but they are now realising it is the most important resource they have,” Dr Knox said.

When you look under a microscope, soil life is extremely abundant.

A single gram of soil can contain more microbes than the number of people on the planet. That same gram of soil can contain more different species of bacteria than the combined different species of mammals on the planet.

“Soil is a wonderful living ecosystem, and the more organic matter with nutritional value we can contribute to it, the better it will be,” Dr Knox said.

He praised Australian cotton farmers for digging deep, to improve their on-farm soil health and for coming up with new ways to help close the fashion circularity system, such as the Cotton Circularity Farming Project.

The project has gained traction globally, with Dr Knox burying underwear in West Africa to compare different farming systems and also look at improvements in soil health between the systems.

Dr Knox, who is also the coordinator of the Cotton Hub at UNE, works with the cotton industry and is funded by the Cotton Research and Development Corporation.

If you bury your underwear, be sure to photograph the stages and share them on social media using the hashtag #soilyourundies


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