Fern fern ("Onoclea sensibilis"). Giant water fern ("Salvinia molesta") is one of the world's worst aquatic weeds. The important fossil fuel coal consists of the remains of primitive plants, including ferns. Ferns have been studied and found to be useful in the removal of heavy metals, especially arsenic, from the soil. Other ferns with some economic significance include: The study of ferns and other pteridophytes is called pteridology. A pteridologist is a specialist in the study of pteridophytes in a broader sense that includes the more distantly related lycophytes. Pteridomania is a term for the Victorian era craze of fern collecting
Vice-county Census Catalogue of the Vascular Plants of Great Britain Druce, which was published in 1932. The comprehensiveness of the work has been questioned by Hannah (2005), citing the Clyde Isles (vice-county 100), where he was able to trace 166 species for which there are records which he believed to be reliable, but which are not among the 891 listed for that vice-county. An errata list, correcting entries for 29 taxa, was published in "BSBI News" no. 97 p. 60 Vice-county Census Catalogue of the Vascular Plants of Great Britain The Vice-county Census Catalogue of the Vascular Plants of Great Britain () is an A5 softback book produced in 2003