Physiognomy and Structure: Vegetation is predominantly dwarf-shrubs or herbaceous (vascular or nonvascular) plants with a moss-dominated ground layer. Stunted trees may be present or a mosaic of patches of stunted trees amongst the mostly herbaceous area.

Floristics: Herbaceous species include Carex anthoxanthea, Carex aquatilis var. dives (= Carex sitchensis), Carex pauciflora, Carex pluriflora, Comarum palustre, Cornus canadensis, Dodecatheon pulchellum, Drosera rotundifolia, Equisetum fluviatile, Eriophorum angustifolium, Geum calthifolium, Nephrophyllidium crista-galli, Parnassia kotzebuei, Rubus chamaemorus, and Sanguisorba menziesii. Moss species include Philonotis fontana var. americana, Sphagnum austinii, Sphagnum fuscum, Sphagnum henryense, Sphagnum mendocinum, Sphagnum pacificum, Sphagnum papillosum, and Sphagnum rubellum. Liverworts include species of Marsupella, Nardia, Scapania, and Siphula. Shrub species include Andromeda polifolia, Betula nana, Empetrum nigrum, Kalmia polifolia, Ledum groenlandicum, Ledum palustre ssp. decumbens, Myrica gale, Salix pulchra, Vaccinium cespitosum, Vaccinium oxycoccos, and Vaccinium uliginosum. Stunted (<5 m) tree species, if present, include Callitropsis nootkatensis (= Cupressus nootkatensis), Picea sitchensis, Pinus contorta var. contorta, Pinus monticola, Tsuga heterophylla, or Tsuga mertensiana. Along the coast, Pinus contorta does not occur north of Juneau in southeastern Alaska; however, further inland it does occur much farther north in the Yukon Territory, where its presence in bogs and fens are part of ~Western North American Boreal Acidic Bog & Fen Group (G360)$$. Floristic information summarized from the following sources: Shacklette et al. (1969), Eyre (1980), Banner et al. (1986, 1988, 1993), DeMeo et al. (1992), Viereck et al. (1992), Kunze (1994), Talbot and Talbot (1994), Martin et al. (1995), Shephard (1995), DeVelice et al. (1999), Boggs et al. (2003, 2008a, 2008b), MacKenzie and Moran (2004), Talbot et al. (2006), and Fleming and Spencer (2007).

Dynamics:  Much literature documents the formation and succession of peatlands in boreal, temperate and Pacific coastal settings (Banner et al. 1988, 2005, Mitsch and Gosselink 2000, and many others). These processes tend to take several hundreds to thousands of years, are well-documented and will not be repeated here. The purpose of this section is to discuss dynamics from disturbance. Natural disturbance events along north coast peatlands play an important role in slowing and reducing organic matter accumulation on specific types of sites. The main types of natural disturbance on the north Pacific coast are landslides, windthrow, and fluvial activity (Banner et al. 2005). Peatlands on steep slopes experience landslides and windthrow events which tend to mix soil and slow the buildup of organic layers. On more gentle terrain, disturbance is less frequent, which allows for a deep accumulation of organic matter. Disturbance here is of small and localized scale. Large-scale disturbance such as major blowdown or severe fire are infrequent (>1000 years).

Fire, when it does occur, stimulates growth of mosses that prefer bare substrates, and "re-starts" a successional sequence of different mosses and vascular plants. Fires also increase nutrient availability and may temporarily create a carbon sink. Fire scars on stumps within herbaceous bogs and fens have been observed, pointing to a need for more study (Banner et al. 2005, J. Rocchio pers. comm. 2013). It has been documented that Native Americans burned herbaceous wetlands of the Olympic Peninsula annually to keep trees from invading wetland openings (Anderson 2009). Logging has also been shown to increase Sphagnum growth, through increased sunlight availability (Banner et al. 2005).

Landslides, fire and changes to water table depth and water source will alter the amount, composition and competition of peatland moss and higher vascular plant species. Fire can remove surface vegetation in dry seasons and stimulate the growth of Sphagnum spp. such that hummocks develop where once a depression occurred (Banner et al. 1988), shifting the small-scale local mosaic of swale and hummock within peatland occurrences. Lowering the water table can allow trees such as Pinus contorta, Tsuga heterophylla and Betula papyrifera to expand into peatland areas. Disturbance may bring the influx of mineral-rich waters from surrounding uplands (particularly along drainage channels), and flora characteristic of bogs is replaced by fen plants such as Spiraea spp., Salix spp., Pyrus spp., Juncus spp. and Carex spp. (Banner et al. 1988). Succession of mined peatlands depends on the degree of humification of the remaining substrate and hydrology. On unhumified peatmoss Sphagnum spp., Drosera rotundifolia, Rubus chamaemorus, and Ledum groenlandicum can regenerate and new Sphagnum peat can accumulate in pits and pools after mining (Banner et al 1988).

In addition to disturbance, there are natural cycles and interplay between the advancement and retreat of peat levels (the buildup of peat that alters depth of rooting zone relative to groundwater, or decrease in peat depth from an increase decomposition due to drought) and encroachment peat into surrounding uplands (paludification) or the reverse, surrounding upland species that may shade out moss species. Generally the greatest (annually measurable) change generally occurs on the edges of fens and bogs and at the tops of hummocks. These small-scale dynamics depend on the type of wetland and specific local site characteristics that cannot be generalized in a group description. Some examples are given here. In Alaska, species that dominate the early stages of succession in newly formed ponded basins include Equisetum variegatum, Equisetum fluviatile, and Comarum palustre, while Sphagnum species invade the surface and help in forming peat. Acidic and nutrient-poor-tolerant vascular species eventually dominate such sites, such as Myrica gale, Empetrum nigrum, Vaccinium uliginosum, Andromeda polifolia, and Vaccinium oxycoccos. The late-successional stage of a peatland supports various community types, depending on the pH, waterflow, and nutrient status of a site, such as Myrica gale / Empetrum nigrum and Picea sitchensis / Sphagnum plant associations. Peat buildup, patterned ground, and changes in water table are recurrent aspects of peatland development rather than unidirectional successional events. For this reason it is unlikely that any of the late-seral peatland communities are stable in the sense of climax vegetation (K. Boggs and T. Boucher pers. comm. 2008). In Washington, some fens can be indefinitely maintained by groundwater discharge; sometimes succession from rich fen to poor fen/bog may occur in these situations but often is dependent on water chemistry and level of discharge and fire (J. Rocchio pers. comm. 2012).

Monitoring peat wetlands is an important source of information as to whether observed changes are due to natural climatic or successional cycles or direct changes of water sources by human hands, or other indirect effects of human activity that may cause sedimentation, draining, flooding, or other changes to peatlands.