Sphagnum ericaceous shrubs, as well as orchids and carnivorous plants. "Sphagnum" and the peat formed from it do not decay readily because of the phenolic compounds embedded in the moss's cell walls. In addition, bogs, like all wetlands, develop anaerobic soil conditions, which produces slower anaerobic decay rather than aerobic microbial action. Peat moss can also acidify its surroundings by taking up cations, such as calcium and magnesium, and releasing hydrogen ions. Under the right conditions, peat can accumulate to a depth of many meters. Different species of "Sphagnum" have different tolerance limits for flooding and pH, so any one peatland
Moss in cities. Examples would be "Rhytidiadelphus squarrosus", a garden weed in Vancouver and Seattle areas; "Bryum argenteum", the cosmopolitan sidewalk moss, and "Ceratodon purpureus", red roof moss, another cosmopolitan species. A few species are wholly aquatic, such as "Fontinalis antipyretica", common water moss; and others such as "Sphagnum" inhabit bogs, marshes and very slow-moving waterways. Such aquatic or semi-aquatic mosses can greatly exceed the normal range of lengths seen in terrestrial mosses. Individual plants or more long are common in "Sphagnum" species for example. Wherever they occur, mosses require liquid water for at least part of the year to complete