You cannot force people to protect trees, wetlands, top soil, water or indeed other species.

Contamination can extend from top soil down to ground water.

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

When any pipeline is made, we strip the top soil.

Clear off all loose top soil within an area slightly larger than the size of the workshop.

The top soil on the steep slopes is very thin.

The acid made a strong solution in all the top soil.

After an island is filled in, it can be covered with several inches of top soil.

The area was then back filled with top soil.

Over 25 million cubic feet of top soil from grazing land alone was moved.