In addition to the more noticeable flowering plants and tall trees that cover Gillies Hill, are a host of organisms often overlooked. Mosses (also known as Bryophytes) of 48 species (including 5 varieties) in 19 families grow throughout the hill. The heavily carpeted star moss (also known as common haircap moss) population near the Wellingtonia Grove is an especially fine example of this life form. Star moss is found in forests, peat bogs, and moorland throughout the Northern Hemisphere. Liverworts (also known as Marchantyphytes) of 22 species (including two varieties) in 15 families on the hill are found in abundance at the entrance to the central mine.