Soils are one of the most biodiverse ecosystems on the planet. We know there are earthworms in soil because we can see them, although most people may not know there can be as many as 50 in a square foot of healthy soil.
Plant roots give back to the soil. This amazing array of microscopic life exists because plant roots do much more than take up nutrients.
There are more than 20,000 types of soil in the U.S. "I think one thing that is fascinating to me about soil is how diverse they are,"said Gaskin. "I think people don't think about what is underneath their feet."
The largest U.S. soil type is in prairies. Prairie soils, Gaskin added, are the most extensive type of soil in the United States. Called Mollisols, they cover 21.5 percent of the country's land mass.
Soils can have beautiful colors. Healthy soils aren't always dark brown. They also can have beautiful shades of blue and pink.
Digging busts up everyone's home. Gaskin urges gardeners not to get too caught up in the numbers of microbes in the soil.
Busted-up homes release carbon dioxide. Good soil contains something else we can't see: tiny pores woven through the aggregates of sand, clay, silt and other matter that make up soil.
Healthy soil takes hundreds of years to form. It takes a long time to restore soil that has been destroyed through carelessness or less-than-optimal gardening practices. "I have heard it takes a thousand years to form an inch of top soil," she said.
Be patient when trying to improve your soil. Gardeners typically try to improve the organic matter in their soil by adding mulch and amendments.
Cover crops benefit the soil — in more ways than one. Scientists are learning more and more that keeping a living root in the soil provides a healthy habitat for soil microbes.
Meet soil's natural rototiller — the earthworm. Compost is a very stable form of organic matter and is a great amendment because over time it will enrich the soil and hold down weeds — something organic herbicides are not good at.
Old agricultural practices didn't do soils any favors. Gaskin thinks the greatest harm humans have done to soil has been though recent agricultural practices that have increased erosion — "recent" as measured against the timeline of human existence.
Georgia's red clay is a subsoil exposed by erosion. Another result from constant plowing can be seen in Georgia's famous red clay, which gets its rust color from oxidized iron.
Soils have a huge impact on water quality and quantity. Soils have had a huge effect on the whole ecosystem, including water quality and quantity, Gaskin said.
You don't have to be a soil nerd to appreciate good soil. Gaskin doesn't think you need to share her passion for soils.
It greatly reduces flood risk by storing up to 9200 tonnes of water per acre. In total that’s about 0.01% of the Earth’s total water.
As already mentioned 50% is air and water, the other 50% is broken rock and decaying plants and animals.
The amount of sand, clay and silt is what gives different soil types their various textures. Most soils are a mix of all three.
Worms enrich topsoil by feeding on organic material in the soil and converting it into nutrients for plants.
Soil is at the bottom of the food chain, yet it is the cornerstone of life on earth.