Soil Your Undies for Sustainability?!

Soil vs. Dirt, Biodegradation, and Landfills

Last month, Sustainable Contra Costa hosted a showing of the highly acclaimed documentary Common Ground, which depicts the "Soil Your Undies Challenge." This experiment playfully challenges participants to learn about the power of healthy soil by burying men’s underwear and observing the results of biodegradation. If after 60 days the underwear has deteriorated, then the soil is healthy and has done its job of breaking down the cotton through good microbes and bacteria. If the underwear is largely unchanged, one can assume the soil is actually just dirt. Which might bring some of you to ask….

Is there a difference between soil and dirt? When local Master Gardener Marian Woodard educates students on the merits of heathy soil, she says a quick phrase to remember the difference between the two is, “Dirt is inert, but soil roils - with life!”

SOIL: Soil is a dynamic and living system of decaying plant and animal matter. Healthy soil cultivates healthy plants and contains a diverse ecosystem of microorganisms with armies of bacteria, fungi, and earthworms. Additionally, the texture of “loamy” soil is an ideal combination of sand, silt, and clay, with air pockets that allow roots to breathe. Setting up nature to succeed and do its thing without intervention is best, but if ideal conditions don’t exist, gardeners may be tempted to rely on a never-ending cycle of harsh chemicals that are toxic to organisms, wildlife, and humans. A tried and true effective, non-toxic, long-term solution to amending soil is using compost. Healthy soil also resists erosion, cycles nutrients, and stores water. The United States Department of Agriculture (USDA) has invested $20 billion towards soil health!

DIRT: Dirt is essentially dead matter. It may have some of the same components and structure of soil, but it lacks organic matter or a living ecosystem that is essential to plant growth. Dirt is often dry and compact, causing plants to struggle to grow. Farmers and gardeners who plant in dirt rather than soil must add nutrients to compensate for an otherwise lifeless base and often resort to synthetic fertilizers and chemicals in order to coax growth out of plants. This chemical intervention of toxic fertilizers, pesticides and herbicides (e.g. glyphosate aka Round Up) provides a relatively quick solution that may “bear fruit” but kills off beneficial microorganisms and predators that would eventually turn dirt into soil and keep it (and you) healthy for the long-term.

Getting back to those undies…The “Bury Your Undies” challenge was created by a group of Oregon farmers who wanted to raise public awareness about the advantages of regenerative agriculture over conventional farming practices such as tilling the soil. Tilling is a short-term solution that disturbs beneficial microbes that create nutrient dense soil and keeps sequestered carbon in the ground rather than releasing it into the air, which contributes to climate change. Tilling is destructive to microorganisms and beneficial decomposers like earthworms, exposes the soil to too much oxygen, and reactivates buried weeds among other things.

You can try the undies challenge yourself! Just bury cotton undies horizontally three inches deep (mark the spot!) and wait 60 days for microbes to do their job. Hopefully it will be in tatters when you dig it back up! Discover how healthy your soil is and learn a little about biodegradability too.

What does biodegradable mean anyway? The EPA defines biodegradability as the ability of a substance to be broken down physically and/or chemically by microorganisms and converted into simpler compounds like carbon dioxide, water, and biomass. Unfortunately, many common household objects such as plastic don’t biodegrade easily, thoroughly, or quickly. With the average American citizen generating over four pounds of waste daily, it becomes more imperative to reduce waste wherever possible. It takes a lot of Father Time to break down objects in overcrowded landfills. There are junk collectors like Junkluggers who pick up difficult to discard garbage and seek opportunities to repurpose, donate, and recycle them whenever possible.

The problem with landfills…The United States has over 3,000 active landfills, and these take up 1,800,000 acres of habitat that displaces local flora and fauna. Communities near landfills also experience decreases in housing values due to landfill contaminants that leak into groundwater systems and pollute drinking water sources.

We’re on track to run out of room in landfills within 18 years. There are already 10,000 closed landfills (full or decommissioned), but even worse, there are illegal landfills that hold more than 40 percent of the waste worldwide and leak toxic chemicals like lead or mercury into the surrounding soil.

Landfills are required to have plastic or clay linings but produce a liquid called leachate, which contains high levels of ammonia. When leachate leaks out of the linings and into ecosystems, it converts into nitrates, which deplete oxygen supplies. This process of “eutrophication” creates dead zones where animals and some plant life cannot survive. Leachate also contains mercury and other toxins that contaminate water sources.

Using sustainable gardening practices to keep soil healthy, reducing waste, and buying selectively go a long way in keeping our bodies and our planet healthy! Here are some eye-opening figures for inspiration.

How long it takes common objects take to biodegrade:

Plastic/Food-Related Items

Aluminum cans (8 – 200 years)

Tin cans (50 – 100 years)

Ziplock/grocery bags (1,000 years)

Straws (400 years)

Wrap (1,000 years)

Bottles (10 to 1,000 years)

Coated milk cartons (5 years)

Six-pack plastic rings (up to 450 years)