To me it was the flat surface that I walked on.

I've been thinking a lot more about it these days and what I learned has

surprised me.

I learned that soil is like the earth's skin

that lies between the

sky and it's rock core.

It's where plants keep tenuous grip with their roots,

as they harvest the sun's energy with their leaves.

I begin to realize that soil is alive.

That a handful of good soil contains more living things than all the human

beings that were ever born.

It dawned on me that without soil

life as we know it would not exist.

If soil is alive

I wondered if soil could die.

I visited with Pam Thomas and spoke to her about this.

A recent historical example is the Dust Bowl.

In the early part of the 1900's homesteaders plowed

millions of acres of prairie lands in order to plant crops, mostly wheat, because

wheat was bringing very high prices during the

World War one wheat boom.

Well because of this intensive cultivation

uh... the delicate balance - the ecosystem- was essentially destroyed - you know you

had the plants, the animals and the micro-organisms

to the point of where the soil no longer was able to function.

So as the wet years of the twenties gave away to the

drought of the

thirties,

the soil, which

no longer had the natural anchors to keep the soil in place, became very

susceptible to wind erosion.

In fact in the nineteen thirties

dust storms would start the great plains and would move cross-country to places like

Boston and DC....

Meanwhile in the southern US piedmont,

plowing and monoculture crops destroyed soil,

causing massive gully erosion.

Some of these gullies are still visible today.

No wonder FDR said that

"the nation that destroys its soil, destroys itself."

These were dramatic examples of soil destruction,

and I got to thinking how we were doing today.

We're still losing soil today. It's not as obvious to us today as it was in the Dust

Bowl thirties

but it's an ongoing crisis because....

the bottom line is, we are feeding more and more people on fewer and

fewer acres.

We're literally losing ground.

The nationalist Aldo Leopold warned us that one of the dangers of

living away from the land

is that we are inclined to think that our breakfast comes from the grocery store ...or a carton.

This got me to wondering how much soil we had to feed

our planet.

My soil scientist friend Jackie helped me understand this. Imagine for a moment

that the earth is this apple... seventy-five percent of the earth is covered by water...

Now half of the dry land on our planet is too hot or too cold

to produce food for humans.

Of this amount, about half is too rocky, steep or too shallow to produce

food.

It doesn't take a rocket scientist to figure that there's not much left

over.

And then what we have left is under pressure from things like urban sprawl

and erosion.

It takes five

hundred years to form an inch of soil,

something that can be destroyed in a few minutes,

and that worries me.

Leonardo DaVinci said that we know more about the movement of celestial bodies

than about the soil underfoot...

I'm guilty as charged

but i'm not going to leave it that way.

Join me in the rest of the series to find out what soil really is and what it

means to us...

perhaps if we learned more about soil we'd be better eqiupped to take care of the

planet.

If life is we know it depends on the soil,

it stands to reason that what happens below the soil's surface has a profound

influenced on what happens above the surface.

My knowledge of soils needed to run deeper.

The people that could help me do this were the soil scientists -

their work is to look beneath the surface into this life-giving, yet unseen

world.

Each day in the field is an adventure of discovery for them -

they have their own vocabulary and they love the feel of dirt in their hands.

this was the soils dream team, and they would be my teachers for the

next few weeks.

Dennis is a veteran who has mapped over a million acres of soils in his lifetime.

Lance and Emory are also seasoned soil explorers who have discovered a new soil

series that bears their respective names.

This was going to be fun.

the first thing they showed me was how the soil was formed.

This happens when weather and living plants and animals breakdown loose rock,

called parent material.

Parent material is typically weathered bedrock that over time becomes the main

mineral component of the soil.

It looks like rock when you dig it out, but as you can see

it's very fragile

massive structure, breaks easily.

Dennis took me to a road cut to show me that overtime, soil is formed in layers called horizons.

These horizons tell us about their history

and they can also give us clues about their future.

This is the A Horizon or the surface layer.

Look at all those roots in there.

That's wonderful.

Dark colors caused by the organic matter in there.

In here we have what's called the E Horizon, capital E.

Fairly light in color,

more sandy in texture

and down below it,

is our B Horizon

that contains much more clay and you can see

it's much more red down here, too.

Each soil horizon has unique properties

like depth, color or clay content.

When these horizons are layered on top of each other over time,

they form soil

profiles which can be identified by name.

they are often named for the place they were first identified, like Norfolk

or Durham.

When it comes to looking below the soil's surface, nothing is as effective as a

good old-fashioned soil auger.

You'll never find these guys in the field without one-

I guarantee it.

Now I began to see how soil profiles can tell their story,

layer by layer.

this is a soil profile

put into a long tray so we can look at it a little

easier that pulling it out with the auger.

In this hand here

you'll see this is the A Horizon

and you'll see it is much darker cause it contains

organic matter in here.

This is the A Horizon or the surface layer. This is eight or ten inches below the surface

and see how red this is?

All soils contain iron and we

know if we put a piece of iron

outside for two weeks it turns rusty.

This is rusty soil.

Rusty soil, how about that?

So each color has a different meaning-

bright reds and yellows mean that a soil is well-drained

there's more oxygen

in the soil to oxidize or rust the iron in the soils.

Grey colors on the other hand, mean the soil is waterlogged for most of the year

because there is less oxygen to get at the iron.

A dark brown color means more organic matter

which is mostly in the A Horizon or topsoil.

we can use the Munsell Color book to classify the exact color of the soil.

We take the

soil ped

and put it behind the book

and find the colorship that it most resembles.

I'm going to say that it's that color there

2.5 YR 4 8

2.5 YR 4 8 by the way

is a more precise way of saying "red".

Dennis also pointed out to me that soil depth is another way

to identify soils.

This is the "Cecil series" because the clay content

extends below a thirty inch depth.

If this clay content decreased above a a thirty inch depth

it's called the "Pacolet series".

They're kissing cousins.

Whoa! kissing cousins?

It turns out that if two soils have similar color and clay content,

but different depths,

they'd be named differently.

At this point I knew enough to see how you could identify a specific soil series.

I was now ready for Lance and Emory to show me their newly discovered soil -

it's named the Brewback series.

Right there, about 22 inches

we just starting to barely nip on the CR material.

You can hear the grind and feel it in the auger.

Right here we have the A Horizon.

It's about six inches thick and it's a fine, sandy loam.

Then we get into the B Horizon, which is a heavy clay.

And here, about

twelve or fifteen inches, we have the uh...

the grey colors

coming in, and for a Brewback soil we have to have the grey colors within

the top ten inches of the B Horzion.

As we move on down the profile about twenty inches, we get the sandy, clay loam,

which is the B-C horizon, which is a transition between the B Horizon and the parent material.

By this time, I had seen a few soil series,

each with its on color, depth, and clay content -

each with its own personality if you will. It turns out that soil scientists have

identified and mapped over nineteen thousand different soil series in the

country.

That sounds like a huge effort -

I had to find out who was doing the work

and why it is so important.

I found out that the massive effort of identifying and mapping soils

is known as the soil survey.

The body of information resulting from this ongoing effort, also known as

the soil survey,

is available in hard copy and online at the web soil survey.

It's an inventory of soil maps, soil properties, suitabilities and

limitations.

I was reminded that what happens beneath the surface of the soil ultimately

affects everything above its surface.

Everything.

That's what makes the soil surveys

so important to any land management decision, from farming to disaster

recovery planning.

I drove out to Lee County to find out

who the people were behind all this work,

and how soils were mapped.

Charlie is a soil scientist who is responsible for the upkeep of about

eleven million acres of soil survey.

Most of this...all of

South Carolina has been mapped,

so what we're doing is updating all

the older soil surveys.

He offered to take us through the process of making a soils map in the

field,

and I asked him to sketch out the day for us.

One of the things we do,

when we go through the process of making the soil map

is to stand and just look at the area

and take in the whole landscape itself. and you can see out in this part of the world,

that some areas of it are concave, some of it are more convex.

So essentially what we do

is to stand out here and note where these areas are,

dig the holes,

identify the soils,

and label them on the map using alpha-numeric symbols.

The finished product looks like this.

This is the same area that we're standing in, and

we can see that these soil lines delineate the different tones on the map.

The first hole we dug was on a slight rise...

we then moved over to a slightly lower area only three hundred feet away and dug another hole.

Charlie showed me the

difference between the two soils that was so close to one

another, and how

land form influenced them.

This soil in the front,

is the "Rains Series".