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
Solar power plants in the Mojave Desert preserved, but the solar industry is mainly interested in areas of the western desert, "where the sun burns hotter and there is easier access to transmission lines", said Kenn J. Arnecke of "FPL Energy", a view shared by many industry executives. Concentrating solar plants in the Mojave Desert have brought up issues of water use, because concentrating solar power plants with wet-cooling systems have high water-consumption intensities compared to other types of electric power plants; only fossil-fuel plants with carbon-capture and storage may have higher water intensities. A 2013 study comparing various sources of electricity found that the median water