It should remove last fall's leaves, smaller twigs and crumbs of surface soil.

The water below ground is actually helping to keep the surface soil in place.

It had been so well used that it was cut more than a hand's breath below the surrounding surface soil.

The species is able to exploit high levels of nitrogen in surface soil to achieve local dominance.

To germinate, simply sprinkle seeds on the surface soil and press down.

These roots range between 1 to 3 millimeters and grow through the water column into the surface soil.

We do not need the poisonous surface soil to raise food.

The appearance of the surface soil is frequently very deceitful.

The hard surface soil will be broken up, to a depth of two feet.

It was a ritual cleansing of more than surface soil.