GeoGraph - photograph every grid square

These small piles of stones protect the entrance to the deep vertical holes formed by anecic earthworms, such as the Common Earthworm (Lumbricus terrestris). Numerous mounds are seen here on arable land with a thin crop of kale. The soil is a stony medium loam of the Crediton Series, subgroup 5.41, typical brown earths in the national soil classification.