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
International Union for the Protection of New Varieties of Plants agriculture for export is increasingly recognized as being unwise. Second, given the lack of empirical evidence to support this, it would make sense to encourage debate, exchange of knowledge and research on the impacts of UPOV type plant variety protection on farming, food, human rights and other public interest objectives. However, UPOV seems to be resisting this, for instance by keeping meetings secret, not making its documents available and [refusing farmers' organisations observer status with UPOV. A recent study by Professor Graham Dutfield exploring the role of UPOV concluded that UPOV's governance falls short in many different ways. In addition,