Ask Lyn: What Makes Soil “Healthy?”

Dear Lyn,

Recently, I saw a billboard advertising “Healthy Soils Clean Water.” It had the TWF logo on it, so I know your organization must be involved somehow, but I don’t get the connection. Isn’t soil just…dirt? What makes it “healthy” or “unhealthy?” And what does that have to do with water? 

Signed,

Soil Curious Sam

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Dear Sam,

Let’s start with “dirt” versus “soil.” You might hear those words used interchangeably, but they’re not the same thing. Dirt is made of materials like sand, clay, and silt. Soil contains dirt–and so much more! Soil is actually an ecosystem that includes living creatures like earthworms, fungi, bacteria, and other microorganisms. It also contains organic matter from plants, insects, and animals. As that organic matter decomposes, it releases nutrients plants need to grow. 

“Healthy” soil has all of those ingredients, plus air and water. It’s full of life, and it supports life! You can see, feel, and even smell its aliveness. Scoop up a handful of soil and look for worms or other critters. Feel its texture–soil with lots of organic matter tends to be dark, crumbly, and a little moist. Give it a sniff. Does it smell earthy or sweet? That’s healthy soil.

So why does The Watershed Foundation, a nonprofit focused on water quality, care about soil? Because healthy soil promotes abundant, healthy water in so many ways! Here are just a few.

• Healthy soil acts like a sponge. It absorbs, stores, and allows water to gradually infiltrate. That means less water runs off the land, carrying sediment and other pollution into our waterways. It also helps replenish our groundwater supply, which we rely on for drinking water–super important in dry or drought conditions, like we’ve faced this year.

• Healthy soil acts like a filter. Biological and chemical processes, plus minerals, microbes, and all those teeny microorganisms–all work together to help clean and detoxify water as it passes through soil. 

• Healthy soil is naturally nutrient-rich. That’s great for plants and the people who grow them–and for water quality. When soil lacks enough nutrients, farmers and gardeners may need to supplement with fertilizer. Excess fertilizer can run off the land and into our streams and lakes, triggering aquatic weed overgrowth and algae blooms. Less fertilizer on land means less fertilizer in water.

The billboard you mentioned is part of TWF’s Soil Health Initiative. That program offers technical and financial support for farmers working to build healthier, more productive soil through low or no-till planting, cover crops, and other methods. We try to help them find solutions that are good for the land, good for the water, and good for their farming operations. 

About 76% of land in our watershed is used for agriculture. Clearly, farmers play a big role in protecting our local land and water from pollution–but soil health isn’t just farmers’ responsibility! We can all do our part. Do you have a yard? Consider replacing some of your lawn with native plants, or just add native plants to your landscaping. Do you grow a garden? Try planting cover crops, using compost, and tilling the soil as little as possible. If you do use fertilizer, pesticides, or herbicides, try not to use more than is necessary. You can also reach out to your county Soil and Water Conservation District for ideas and support. Many offer helpful resources and services, like soil testing. Each of these actions, however small, helps build soil health and protect water quality in some way.

Still curious about soil, Sam? Check out Clear Choices Clean Water. You’ll find loads of information, resources, and ways to make a difference!

Lyn