Sphagnum fuscum an indicator of high depositions of sulphur and nitrogen in substrates. "S. fuscum" grows in areas with high sulphur and nitrogen depositions, which is concomitant with the decreased pH of the soil. Sphagnum has also been used historically for medicinal purposes. The moss itself has antimicrobial properties, and was therefore used as an effective filler for wounds to prevent infection. It also retains large amounts of moisture, which was quite useful in keeping the skin around a wound moist to prevent tissue death. Sphagnum fuscum Sphagnum fuscum, the rusty bogmoss or rusty peat moss, is a peat moss found commonly
Carnivorous plant more or less than this optimum will take up less carbon dioxide than an optimal plant, and hence growing less well. These plants will be at a selective disadvantage. At zero investment the growth is zero, because a non-carnivorous plant cannot survive in a habitat with absolutely no soil-borne nutrients. Such habitats do not exist, so for example, "Sphagnum" absorbs the tiny amounts of nitrates and phosphates in rain very efficiently and also forms symbioses with diazotrophic cyanobacteria. In a habitat with abundant soil nutrients but little light (as shown above), the gross photosynthesis curve will be lower and flatter,