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I have to admit I tend to take dirt a little bit for granted.

It's something I think about mostly if I track it in on the rug or if I need to

wash it off the dog after we've gone for a hike. So in honor of World Soil Day, I am here in the

backyard digging in the dirt.

In this handful of soil that I just shoveled up,

you know first glance it looks exactly like what you'd think. It's brown and

crumbly. It's got some clay consistency because it just rained. But as I start to

break it apart and look closer, I see all sorts of things.

There are earthworms, there are little white bug eggs like caviar.

There's rotting little chunks of wood, and then just this web of roots and fungi all

twisted together. If you put you know a handful of healthy soil say a forest topsoil if you will, undisturbed on the

palm of your hands and look at it. Just think about how that amount of soil

holds you know up to 10 billion individual living things in it.

Wow!

And those 10 billion individual things can come from anywhere up to five,

maybe even more, thousand different species.

So we're talking about not just a lot of life, but a lot of diversity of life.

This is Asmert Asifau Berhe, a professor at the University of California Merced.

She's also currently serving as the Director of the Office of Science at the Department of Energy, but her first love is that earthy stuff beneath our feet.

Just don't call it dirt.

As a soil scientist, I don't like the D word. I think calling soil...

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