Natural Communities of NH -- Photo Guide

Water willow - Sphagnum fen  (S3)


formerly water willow - Sphagnum lagg

Water willow - Sphagnum fens
 occur in peatlands in southern and central parts of the state. They are typically found in wet minerotrophic settings along the interior edge of peat mats (between the mat and open water at the center of the peatland), and also sometimes in moat settings along the upland edge. Average pH is 4.4 and hummocks are usually moderately well developed (average height 0.25 m). Peat is relatively well decomposed near the surface. Average medium shrub height is 0.95 m.

Characteristic Vegetation: Peat mosses (Sphagnum spp.) form the substrate, while water willow (Decodon verticillatus) is the dominant shrub. Other frequent species are silvery sedge (Carex canescens), leatherleaf (Chamaedaphne calyculata), sweet gale (Myrica gale), swamp candles (Lysimachia terrestris), and marsh St. John's-wort (Triadenum virginicum). The peat mosses are notably minerotrophic, and include species such as Sphagnum recurvum, S. flexuosum, S. fimbriatum, and occasionally S. papillosum. Highbush blueberry (Vaccinium corymbosum) is notably infrequent and only present in low abundance. Species such as Sphagnum recurvum and water willow have southern or coastal affinities.



Good examples of this community can be seen at Lynxfield Pond (Chichester), Cedar Swamp Pond (Kingston), Hubbard Pond (Rindge), and Binney Pond (New Ipswich).

Water willow - Sphagnum fens often occur as part of larger medium level fen systems, and sometimes as part of kettle hole bog systems or poor level fen/bog systems.


Water willow - Sphagnum fen at Cedar Swamp Pond in Kingston (photo by Ben Kimball)
Water willow - Sphagnum fen at Cedar Swamp Pond in Kingston (photo by Ben Kimball)

water willow - sphagnum fen (photo by Dan Sperduto)

Water willow - Sphagnum fen 
near Pawtuckaway State Park
(photo by Dan Sperduto)

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