Sphagnum cuspidatum capitulum. "Sphagnum cuspidatum" is a dominant species in the bogs that it inhabits. In wetlands, they consume methane through symbiosis with partly endophytic methanotrophic bacteria, leading to highly effective in situ methane recycling preventing large-scale methane emission into the atmosphere. The bacteria are present in the hyaline cells of the plant. Sometimes, Sphagnum moss can be infected with another type of fungus that can cause sporotrichosis. The other fungus can enter the body through cuts or scrapes on the skin, and will then cause ulcerous skin lesions. It is therefore advised to wear gloves and long sleeves when handling sphagnum
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,