topsoil

Those tests typically had been used to determine whether cleanup crews should remove more than the first 6 inches of topsoil.

After previous wildfires, the Army Corps would first scrape 6 inches of topsoil from cleared properties and then test the ground underneath.

The dung beetle, which disperses seeds as it rolls its dung balls, fertilizing topsoil and enhancing biodiversity and engineering its environment, normally orients itself using the Milky Way and the moon.

Federally hired cleanup crews have been removing ash and debris, in addition to a 6-inch layer of topsoil, from buildings burned by the wildfires.

It was eventually supposed to be covered in topsoil and turfed over, and made level with the surrounding fields.