DATE: 11/16/2005                                                 

CONTACT: Claudia Meadows, (803) 266-4105

WRITER: Tom Lollis, (803) 284-3343, ext. 241

Kids learn to appreciate soil complexity at Edisto REC

BLACKVILLE – Consider the ground beneath your feet. Did you realize you’re actually walking on air? That’s because the spaces between individual soil particles are occupied by air. Up to half the volume of a given amount of soil can be air and water.

That’s just one of the neat facts primary school students learned during Soil Science Week at Clemson University’s Edisto Research and Education Center Nov. 7-11.

“We want to teach our children to have an appreciation for the environment, and have respect for soil, one of our most valuable natural resources,” said Claudia Meadows, volunteer coordinator for the Agricultural Heritage Center’s Learning Center at Edisto REC.

A soil profile pit used to teach farmers about soil characteristics was one of the stops for third graders from Barnwell Primary, Bamberg Primary, Richard Carroll Elementary of Aiken and South Aiken Baptist Christian School.

Meadows pointed out layers of soil, visible on the back wall of the pit, with different colors and different thicknesses – like an odd layer cake.

“The top layer is called the O horizon, and it contains organic matter,” said Meadows. Only an inch to an inch and a half thick, it is made up of dead and decaying remains of plant material and animal wastes, all being broken down by bacteria, worms and insects that live in the soil.

Below the O horizon is the A horizon, known as topsoil, about 14 inches thick in the pit at Edisto REC. It’s where seeds germinate and plant roots grow.

“It can take as much as 800 to 1,000 years for an inch of topsoil to accumulate,” she said. “Soil is a living environment. In a double handful of soil you can be holding billions of organisms such as bacteria and nematodes.”

Meadows pointed out that in some parts of the United States, particularly in the Midwest, the topsoil can be as black as a tractor tire and measured in feet. The more fertile high organic soil is uncommon in South Carolina, where topsoil is not nearly as dark nor as thick.

“That’s why they can make higher yields of crops like corn and soybeans in Illinois than we can,” she said. Below the A horizon is the B horizon, also called the subsoil. It’s made up of clay and mineral deposits – like iron, aluminum oxides and calcium carbonate – that it receives when mineralized water drips through the layers above. About 9 inches of clay is visible at the Edisto site.

“Somewhere below all that clay is the parent material from which soil is made – bedrock,” said Meadows. Rock weathers into smaller and smaller pieces from mechanical and chemical processes – freezing and thawing, the action of water and plant roots that work their way into tiny crevices.

Students also visited the Learning Center at Edisto REC for a lesson on soil basics and natural resource conservation. They learned that most of the food they eat has its roots in the soil – whether it’s cereal made from wheat or oats or milk from cows that eat grass and grains.

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