the world > the earth > structure of the earth > constituent materials > earth or soil > kind of earth or soil > [noun] > organic soil > mould > layer
garden mould1573
garden earth1577
staplea1722
staple-soil1847
1847 Jrnl. Royal Agric. Soc.8ii. 317 This is chiefly a deep staple soil.
1856 Farmer's Mag. Jan. 20 His practice never advanced further than to lay bare the subsoil in the intervals' by gathering the staple-soil into the wheat ridges.