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Name: Max
Status: student
Age: 5
Location: N/A
Country: N/A
Date: 2001

What is dirt?

Max: A teacher of mine once said: "dirt is what you track in on your mother's floor, soil is what plants grow in." A scientist would not use the word "dirt" for the surface layer of the ground where plants grow, that is "soil." Soil is made up of minerals that come from rocks, and lots of decaying plant and animal material. It takes a long time for growing things to form rich soil, an average is about 1000 years for every inch of topsoil, but that can be very different from one place to another.

J. Elliott

Dirt is made of finely-ground rocks and decayed organic matter. It is actually very complicated stuff.

Richard E. Barrans Jr., Ph.D.
Assistant Director
PG Research Foundation, Darien, Illinois

Dear Max:

I suggest that you try out the following web site:

It was put together by some real experts on dirt.

Tom Douglas

Dirt comes from two different things. First, when plants and other things die, bugs and worms and other animals help break the plants down into little bits. Dirt that is black and dark has lots of old plants in it. Also, when rocks stay outside in the sun and rain and wind for a long, long time, they start to fall apart into smaller and smaller pieces until they become little tiny grains. That is why some dirt has chunks of rock in it, too. Andrew Johnson

Hi Max...

in a general way, we can call dirt the earth that is the soil of our planet. The soil is made mostly of substances called silicates mixed up with a lot of other substances, so the soil can have different properties, as different colors, for example.

In another point of view, dirt is the opposite of clean, but what is clean? a thing is clean when it has no impurities, no mixtures. When your mom washes your jeans very well, it is clean. Now if you put it on and go to play outside, and run and play, do a lot of things, your jeans becomes dirty, covered with impurities, and must be washed again. So the dirt over it can be a lot of things: earth powder, a piece of ice-cream, ink or colored pencils blots, oil, ketchup, and so on. I mean anything that makes something unclean can be called dirt.

OK? And thanks for asking NEWTON! it was a pleasure answer to you!

(Dr. Mabel Rodrigues)

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