Oswego Lake Watershed Council holds challenge locally to educate Lake Oswegans on soil health.

PMG PHOTO: JONATHAN VILLAGOMEZ - The Oswego Lake Watershed Council held the Reveal Your Undies event July 7 at West Waluga Park in Lake Oswego. Participants brought the undies they received back in April and after two months dug them up to reveal how healthy their soil is based on the amount of fabric that remained. Lake Oswego community members engaged in a unique science project over the past couple of months — one that involved white cotton underwear.

As part of the national Soil Your Undies campaign — which was formed in 2018 by Oregon farmers, working with their local Soil and Water Conservation Districts (SWCDs) and Natural Resources Conservation Service — people bury their 100% cotton underwear to test soil health. Cotton, being a food source for soil microbes, will degrade over a period of time if the soil is healthy.

At the local level this year, the Oswego Lake Watershed Council decided to undergo its own campaign with Lake Oswego residents. The council unveiled the outcomes during a small-scale event July 7 at West Waluga Park.

"The more your undies disappear, the more diverse and nutrient-rich your soil is," said Allie Molen, watershed outreach specialist for the Oswego Lake Watershed Council. "This citizen science activity is meant to demonstrate soil health as an integral component of a healthy urban forest ecosystem."

This past April, the OLWC gave out 103 pairs of plain white "tighty-whities" to families and instructed them to bury the cotton briefs 6-8 inches deep in the soil. They were then asked to wait about two months before digging them up.

"I thought it went fantastic," Molen said. "We had a pretty good turnout."

Families buried the briefs in their gardens or yards and then showcased them on a clothesline at Waluga Park during the unveiling event, which also featured science education and activities.

"We had a pretty good range of pebbly, decomposed underwear that were basically hanging from scraps on the line," Molen said. "We're just really excited to learn more about soil. Soil is absolutely fundamental to life on Earth."

Soil Your Undies

People used a microscope to view small organisms that were found in the soil and also participated in a soil infiltration activity. Stephanie Wagner, a representative with the OLWC, took soil samples from her yard and put them in a jar of water to show how soil aggregates stayed clumped together while other particles fell apart.

Molen said if the soil stays clumped, there's evidence it has more organic matter and microorganisms.

"Soil with high amounts of organic matter can also hold more water, which prevents excess runoff and increases the soil's resilience to drought," Molen said. "Healthy soil can also help mitigate climate change by removing CO2 from the atmosphere and storing it in a carbon 'pool' (carbon sequestration)."

Healthy soil is important for a number of reasons. It requires less fertilization, holds water and carbon better and helps produce healthy crops at a higher yield, among other benefits.

"We had a lot of folks with pretty well-ragged underwear," which indicated healthy soil according to Molen.

Others had their underwear intact.

"There are areas of Lake Oswego that do not have as nutrient-rich soil as others," Molen said.

She added that there are a number of variables that are out of people's control like weather, the amount of shade in a yard and water access.

Molen said the OLWC plans to do this challenge annually and will follow up with participants to build a data set to see if the tips they provided to increase soil health actually helped. The goal is to expand education about the impact of soil on the watershed and urban forest in Lake Oswego.

People can find more information about the challenge on the OLWC's website.

You count on us to stay informed and we depend on you to fund our efforts. Quality local journalism takes time and money. Please support us to protect the future of community journalism.