Then put in a 3- or 4-inch layer of soil.

The gas pressure also supports the soil layers above the field.

A light layer of soil was put over the body and the spot marked.

There was only a thin layer of top soil which could not support many crops.

They stay near the upper soil layer because all the main nutrients are found there.

Keep piling, and add a layer of soil every foot or so.

But, if ice were insulated with a layer of soil, it could last a long time.

About six inches deep, she reached a layer of loose soil and dead leaves.

Then the coals are covered with another layer of soil.

The students also hand tamped over a hundred layers of soil.